Various clean-ups

Change-Id: I53e04a247a25149d9f29135484c0528c706de7d8
Reviewed-by: Michal Klocek <michal.klocek@qt.io>
(cherry picked from commit 8c113ad54b39d26c011a8a127b8dac6c401a9ef3)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

48 files changed, 71 insertions, 151 deletions

diff --git a/src/core/accessibility_tree_formatter_qt.cpp b/src/core/accessibility_tree_formatter_qt.cpp
index 720b28b7d..0f642b947 100644
--- a/src/core/accessibility_tree_formatter_qt.cpp
+++ b/src/core/accessibility_tree_formatter_qt.cpp
@@ -5,11 +5,7 @@
 
 #include <utility>
 
-#include "base/logging.h"
-#include "base/strings/string_number_conversions.h"
-#include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
-#include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "content/browser/accessibility/accessibility_event_recorder.h"
 #include "content/browser/accessibility/accessibility_tree_formatter_blink.h"
diff --git a/src/core/api/qwebenginepage.cpp b/src/core/api/qwebenginepage.cpp
index a726ae56f..3b83a0b97 100644
--- a/src/core/api/qwebenginepage.cpp
+++ b/src/core/api/qwebenginepage.cpp
@@ -10,6 +10,7 @@
 #include "qwebenginefullscreenrequest.h"
 #include "qwebenginehistory.h"
 #include "qwebenginehistory_p.h"
+#include "qwebenginehttprequest.h"
 #include "qwebengineloadinginfo.h"
 #include "qwebenginenavigationrequest.h"
 #include "qwebenginenewwindowrequest.h"
@@ -43,8 +44,10 @@
 #include <QIcon>
 #include <QLoggingCategory>
 #include <QMimeData>
+#include <QRect>
 #include <QTimer>
 #include <QUrl>
+#include <QVariant>
 
 QT_BEGIN_NAMESPACE
 
@@ -1040,7 +1043,7 @@ QAction *QWebEnginePage::action(WebAction action) const
 {
     Q_D(const QWebEnginePage);
     if (action == QWebEnginePage::NoWebAction)
-        return 0;
+        return nullptr;
     if (d->actions[action])
         return d->actions[action];
 
diff --git a/src/core/api/qwebenginepage.h b/src/core/api/qwebenginepage.h
index 3feb275b0..f4cca0582 100644
--- a/src/core/api/qwebenginepage.h
+++ b/src/core/api/qwebenginepage.h
@@ -7,28 +7,29 @@
 #include <QtWebEngineCore/qtwebenginecoreglobal.h>
 #include <QtWebEngineCore/qwebengineclientcertificateselection.h>
 #include <QtWebEngineCore/qwebenginedownloadrequest.h>
-#include <QtWebEngineCore/qwebenginehttprequest.h>
 
 #include <QtCore/qobject.h>
 #include <QtCore/qurl.h>
-#include <QtCore/qvariant.h>
-#include <QtGui/qaction.h>
 #include <QtGui/qpagelayout.h>
 #include <QtGui/qpageranges.h>
+#include <QtGui/qtgui-config.h>
 
 #include <functional>
 
 QT_BEGIN_NAMESPACE
 
+class QAction;
 class QAuthenticator;
 class QContextMenuBuilder;
+class QRect;
+class QVariant;
 class QWebChannel;
 class QWebEngineCertificateError;
-class QWebEngineClientCertificateSelection;
 class QWebEngineFileSystemAccessRequest;
 class QWebEngineFindTextResult;
 class QWebEngineFullScreenRequest;
 class QWebEngineHistory;
+class QWebEngineHttpRequest;
 class QWebEngineLoadingInfo;
 class QWebEngineNavigationRequest;
 class QWebEngineNewWindowRequest;
diff --git a/src/core/api/qwebenginepage_p.h b/src/core/api/qwebenginepage_p.h
index a2aa40ce2..8bdf6de5c 100644
--- a/src/core/api/qwebenginepage_p.h
+++ b/src/core/api/qwebenginepage_p.h
@@ -23,6 +23,7 @@
 #include <QtCore/qcompilerdetection.h>
 #include <QtCore/QPointer>
 #include <QtCore/QTimer>
+#include <QtGui/QColor>
 
 namespace QtWebEngineCore {
 class AutofillPopupController;
diff --git a/src/core/chromium_overrides.cpp b/src/core/chromium_overrides.cpp
index 6130912b6..9fced7915 100644
--- a/src/core/chromium_overrides.cpp
+++ b/src/core/chromium_overrides.cpp
@@ -7,32 +7,15 @@
 #include "web_contents_view_qt.h"
 #include "web_engine_library_info.h"
 #include "base/values.h"
-#include "content/browser/renderer_host/render_widget_host_view_base.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/common/font_list.h"
 #include "ui/base/dragdrop/os_exchange_data.h"
 #include "ui/base/dragdrop/os_exchange_data_provider_factory.h"
-#include "ui/events/devices/device_data_manager.h"
-#include "ui/events/platform/platform_event_source.h"
-#include "ppapi/buildflags/buildflags.h"
 
 #include <QGuiApplication>
-#include <QScreen>
-#include <QWindow>
 #include <QFontDatabase>
-#include <QStringList>
 #include <QLibraryInfo>
 
-#if defined(USE_AURA) && !defined(USE_OZONE)
-#include "ui/base/dragdrop/os_exchange_data.h"
-#include "ui/gfx/render_text.h"
-#include "ui/gfx/platform_font.h"
-#endif
-
-#if defined(USE_OPENSSL_CERTS)
-#include "net/ssl/openssl_client_key_store.h"
-#endif
-
 #if !QT_CONFIG(webengine_webrtc) && QT_CONFIG(webengine_extensions)
 #include "chrome/browser/extensions/api/webrtc_logging_private/webrtc_logging_private_api.h"
 #endif
@@ -43,7 +26,6 @@ void *GetQtXDisplay()
 }
 
 namespace content {
-class WebContentsImpl;
 class WebContentsView;
 class WebContentsViewDelegate;
 class RenderViewHostDelegateView;
diff --git a/src/core/color_chooser_controller.cpp b/src/core/color_chooser_controller.cpp
index 4a3835a67..fcaef2eba 100644
--- a/src/core/color_chooser_controller.cpp
+++ b/src/core/color_chooser_controller.cpp
@@ -65,5 +65,4 @@ void ColorChooserController::reject()
     didEndColorDialog();
 }
 
-
-} // namespace
+} // namespace QtWebEngineCore
diff --git a/src/core/color_chooser_controller.h b/src/core/color_chooser_controller.h
index 96236ff72..7eafc143a 100644
--- a/src/core/color_chooser_controller.h
+++ b/src/core/color_chooser_controller.h
@@ -47,6 +47,6 @@ private:
     friend class ColorChooserQt;
 };
 
-} // namespace
+} // namespace QtWebEngineCore
 
 #endif // COLOR_CHOOSER_CONTROLLER_H
diff --git a/src/core/color_chooser_controller_p.h b/src/core/color_chooser_controller_p.h
index a5669fa3e..45eeb9471 100644
--- a/src/core/color_chooser_controller_p.h
+++ b/src/core/color_chooser_controller_p.h
@@ -18,7 +18,7 @@
 #include <QColor>
 
 namespace content {
-    class WebContents;
+class WebContents;
 }
 
 namespace QtWebEngineCore {
@@ -31,7 +31,7 @@ public:
     QColor m_initialColor;
 };
 
-} // namespace
+} // namespace QtWebEngineCore
 
 #endif // COLOR_CHOOSER_CONTROLLER_P_H
 
diff --git a/src/core/color_chooser_qt.cpp b/src/core/color_chooser_qt.cpp
index 4aa3101b7..de2e833a0 100644
--- a/src/core/color_chooser_qt.cpp
+++ b/src/core/color_chooser_qt.cpp
@@ -5,9 +5,7 @@
 #include "color_chooser_controller.h"
 #include "color_chooser_controller_p.h"
 
-namespace content {
-    class WebContents;
-}
+#include <QColor>
 
 namespace QtWebEngineCore {
 
@@ -21,4 +19,4 @@ QSharedPointer<ColorChooserController> ColorChooserQt::controller()
     return m_controller;
 }
 
-} // namespace
+} // namespace QtWebEngineCore
diff --git a/src/core/color_chooser_qt.h b/src/core/color_chooser_qt.h
index 35ec0b48f..dde9a51ce 100644
--- a/src/core/color_chooser_qt.h
+++ b/src/core/color_chooser_qt.h
@@ -7,11 +7,12 @@
 #include "content/public/browser/color_chooser.h"
 #include "type_conversion.h"
 
-#include <QColor>
 #include <QSharedPointer>
 
+QT_FORWARD_DECLARE_CLASS(QColor)
+
 namespace content {
-    class WebContents;
+class WebContents;
 }
 
 namespace QtWebEngineCore {
@@ -32,7 +33,6 @@ private:
     QSharedPointer<ColorChooserController> m_controller;
 };
 
-
-} // namespace
+} // namespace QtWebEngineCore
 
 #endif // COLOR_CHOOSER_QT_H
diff --git a/src/core/common/extensions/extensions_client_qt.h b/src/core/common/extensions/extensions_client_qt.h
index 6c192dd8e..32a752d95 100644
--- a/src/core/common/extensions/extensions_client_qt.h
+++ b/src/core/common/extensions/extensions_client_qt.h
@@ -10,7 +10,6 @@
 
 #include "extensions/common/extensions_client.h"
 
-#include "base/compiler_specific.h"
 #include "base/lazy_instance.h"
 #include "chrome/common/extensions/permissions/chrome_permission_message_provider.h"
 #include "extensions/common/features/feature_provider.h"
diff --git a/src/core/content_browser_client_qt.cpp b/src/core/content_browser_client_qt.cpp
index 31c1699f8..72bd34d5d 100644
--- a/src/core/content_browser_client_qt.cpp
+++ b/src/core/content_browser_client_qt.cpp
@@ -49,7 +49,6 @@
 #include "url/url_util_qt.h"
 
 #include "qtwebengine/common/renderer_configuration.mojom.h"
-#include "qtwebengine/grit/qt_webengine_resources.h"
 
 #include "profile_adapter.h"
 #include "browser_main_parts_qt.h"
@@ -95,11 +94,6 @@
 #include "location_provider_qt.h"
 #endif
 
-#if QT_CONFIG(webengine_pepper_plugins)
-#include "content/public/browser/browser_ppapi_host.h"
-#include "ppapi/host/ppapi_host.h"
-#endif
-
 #if QT_CONFIG(webengine_spellchecker)
 #include "chrome/browser/spellchecker/spell_check_host_chrome_impl.h"
 #include "components/spellcheck/common/spellcheck.mojom.h"
@@ -433,7 +427,6 @@ void ContentBrowserClientQt::RegisterBrowserInterfaceBindersForFrame(
         content::RenderFrameHost *render_frame_host,
         mojo::BinderMapWithContext<content::RenderFrameHost *> *map)
 {
-    Q_UNUSED(render_frame_host);
     map->Add<network_hints::mojom::NetworkHintsHandler>(base::BindRepeating(&BindNetworkHintsHandler));
 #if BUILDFLAG(ENABLE_EXTENSIONS)
     map->Add<extensions::mime_handler::MimeHandlerService>(base::BindRepeating(&BindMimeHandlerService));
@@ -450,6 +443,8 @@ void ContentBrowserClientQt::RegisterBrowserInterfaceBindersForFrame(
     extensions::ExtensionsBrowserClient::Get()->RegisterBrowserInterfaceBindersForFrame(map,
                                                                                         render_frame_host,
                                                                                         extension);
+#else
+    Q_UNUSED(render_frame_host);
 #endif
 }
 
diff --git a/src/core/content_client_qt.cpp b/src/core/content_client_qt.cpp
index a7619da15..553e4b4c8 100644
--- a/src/core/content_client_qt.cpp
+++ b/src/core/content_client_qt.cpp
@@ -8,7 +8,6 @@
 #include "base/strings/string_piece.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
-#include "base/strings/utf_string_conversions.h"
 #include "base/version.h"
 #include "content/public/common/cdm_info.h"
 #include "content/public/common/content_constants.h"
diff --git a/src/core/devtools_frontend_qt.cpp b/src/core/devtools_frontend_qt.cpp
index 2fda99cbc..7f0168976 100644
--- a/src/core/devtools_frontend_qt.cpp
+++ b/src/core/devtools_frontend_qt.cpp
@@ -29,6 +29,7 @@
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_task_traits.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/browser/devtools_frontend_host.h"
 #include "content/public/browser/file_url_loader.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_handle.h"
diff --git a/src/core/devtools_frontend_qt.h b/src/core/devtools_frontend_qt.h
index 73c55c0cd..bbc867862 100644
--- a/src/core/devtools_frontend_qt.h
+++ b/src/core/devtools_frontend_qt.h
@@ -9,13 +9,9 @@
 
 #include "web_contents_delegate_qt.h"
 
-#include "base/compiler_specific.h"
 #include "base/containers/unique_ptr_adapters.h"
-#include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
-#include "base/values.h"
 #include "content/public/browser/devtools_agent_host.h"
-#include "content/public/browser/devtools_frontend_host.h"
 #include "content/public/browser/web_contents_observer.h"
 
 namespace base {
@@ -23,8 +19,8 @@ class Value;
 }
 
 namespace content {
+class DevToolsFrontendHost;
 class NavigationHandle;
-class RenderViewHost;
 class WebContents;
 }  // namespace content
 
diff --git a/src/core/devtools_manager_delegate_qt.cpp b/src/core/devtools_manager_delegate_qt.cpp
index 139ee2d14..6654ead0e 100644
--- a/src/core/devtools_manager_delegate_qt.cpp
+++ b/src/core/devtools_manager_delegate_qt.cpp
@@ -7,31 +7,19 @@
 // found in the LICENSE.Chromium file.
 
 #include "devtools_manager_delegate_qt.h"
+#include "qtwebengine/grit/qt_webengine_resources.h"
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
-#include "base/memory/ptr_util.h"
-#include "base/strings/string_number_conversions.h"
-#include "base/strings/utf_string_conversions.h"
 #include "content/browser/devtools/devtools_http_handler.h"
 #include "content/public/browser/devtools_agent_host.h"
-#include "content/public/browser/devtools_frontend_host.h"
 #include "content/public/browser/devtools_socket_factory.h"
-#include "content/public/browser/favicon_status.h"
-#include "content/public/browser/navigation_entry.h"
-#include "content/public/browser/render_view_host.h"
-#include "content/public/browser/web_contents.h"
-#include "content/public/browser/web_contents_delegate.h"
 #include "content/public/common/content_switches.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_errors.h"
 #include "net/socket/tcp_server_socket.h"
 #include "ui/base/resource/resource_bundle.h"
 
-#include "qtwebengine/grit/qt_webengine_resources.h"
-
-#include "type_conversion.h"
-
 using content::DevToolsAgentHost;
 
 namespace {
@@ -152,4 +140,4 @@ bool DevToolsManagerDelegateQt::HasBundledFrontendResources()
     return true;
 }
 
-} //namespace QtWebEngineCore
+} // namespace QtWebEngineCore
diff --git a/src/core/download_manager_delegate_qt.cpp b/src/core/download_manager_delegate_qt.cpp
index 60e68a7c1..b5ac6868c 100644
--- a/src/core/download_manager_delegate_qt.cpp
+++ b/src/core/download_manager_delegate_qt.cpp
@@ -3,8 +3,6 @@
 
 #include "download_manager_delegate_qt.h"
 
-#include "base/files/file_util.h"
-#include "base/time/time_to_iso8601.h"
 #include "content/public/browser/download_item_utils.h"
 #include "content/public/browser/download_manager.h"
 #include "content/public/browser/save_page_type.h"
@@ -13,9 +11,7 @@
 #include "net/http/http_content_disposition.h"
 
 #include <QDir>
-#include <QFile>
 #include <QFileInfo>
-#include <QMap>
 #include <QMimeDatabase>
 #include <QStandardPaths>
 
diff --git a/src/core/download_manager_delegate_qt.h b/src/core/download_manager_delegate_qt.h
index b0869d8be..f807301d1 100644
--- a/src/core/download_manager_delegate_qt.h
+++ b/src/core/download_manager_delegate_qt.h
@@ -24,8 +24,6 @@ class DownloadItem;
 
 namespace QtWebEngineCore {
 class ProfileAdapter;
-class DownloadManagerDelegateInstance;
-class DownloadTargetHelper;
 
 class DownloadManagerDelegateQt
         : public content::DownloadManagerDelegate
@@ -65,10 +63,8 @@ private:
 
     uint32_t m_currentId;
     base::WeakPtrFactory<DownloadManagerDelegateQt> m_weakPtrFactory;
-
-    friend class DownloadManagerDelegateInstance;
 };
 
 } // namespace QtWebEngineCore
 
-#endif //DOWNLOAD_MANAGER_DELEGATE_QT_H
+#endif // DOWNLOAD_MANAGER_DELEGATE_QT_H
diff --git a/src/core/extensions/component_extension_resource_manager_qt.cpp b/src/core/extensions/component_extension_resource_manager_qt.cpp
index b1124bd51..d541dea37 100644
--- a/src/core/extensions/component_extension_resource_manager_qt.cpp
+++ b/src/core/extensions/component_extension_resource_manager_qt.cpp
@@ -10,7 +10,6 @@
 
 #include "base/check.h"
 #include "base/containers/contains.h"
-#include "base/logging.h"
 #include "base/path_service.h"
 #include "base/stl_util.h"
 #include "base/values.h"
diff --git a/src/core/extensions/extensions_browser_client_qt.h b/src/core/extensions/extensions_browser_client_qt.h
index 7b3ee1903..e111c1283 100644
--- a/src/core/extensions/extensions_browser_client_qt.h
+++ b/src/core/extensions/extensions_browser_client_qt.h
@@ -9,7 +9,6 @@
 #ifndef EXTENSIONS_BROWSER_CLIENT_QT_H_
 #define EXTENSIONS_BROWSER_CLIENT_QT_H_
 
-#include "base/compiler_specific.h"
 #include "extensions/browser/extensions_browser_client.h"
 #include "mojo/public/cpp/bindings/pending_receiver.h"
 #include "mojo/public/cpp/bindings/pending_remote.h"
diff --git a/src/core/javascript_dialog_controller_p.h b/src/core/javascript_dialog_controller_p.h
index f1bca3eca..8345cd50b 100644
--- a/src/core/javascript_dialog_controller_p.h
+++ b/src/core/javascript_dialog_controller_p.h
@@ -21,6 +21,7 @@
 #include "web_contents_adapter_client.h"
 
 #include <QString>
+#include <QUrl>
 
 namespace content {
 class WebContents;
diff --git a/src/core/javascript_dialog_manager_qt.h b/src/core/javascript_dialog_manager_qt.h
index ac65f89d0..2a587afc7 100644
--- a/src/core/javascript_dialog_manager_qt.h
+++ b/src/core/javascript_dialog_manager_qt.h
@@ -3,7 +3,6 @@
 #ifndef JAVASCRIPT_DIALOG_MANAGER_QT_H
 #define JAVASCRIPT_DIALOG_MANAGER_QT_H
 
-#include "base/callback.h"
 #include "content/public/browser/javascript_dialog_manager.h"
 
 #include "web_contents_adapter_client.h"
diff --git a/src/core/media_capture_devices_dispatcher.cpp b/src/core/media_capture_devices_dispatcher.cpp
index 9775ce3e2..14c7bd62e 100644
--- a/src/core/media_capture_devices_dispatcher.cpp
+++ b/src/core/media_capture_devices_dispatcher.cpp
@@ -7,13 +7,11 @@
 
 #include "media_capture_devices_dispatcher.h"
 
-#include "javascript_dialog_manager_qt.h"
 #include "type_conversion.h"
 #include "web_contents_delegate_qt.h"
 #include "web_contents_view_qt.h"
 #include "web_engine_settings.h"
 
-#include "base/strings/utf_string_conversions.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/desktop_media_id.h"
@@ -23,15 +21,12 @@
 #include "media/audio/audio_device_description.h"
 #include "media/audio/audio_manager_base.h"
 #include "services/network/public/cpp/is_potentially_trustworthy.h"
-#include "ui/base/l10n/l10n_util.h"
 
 #if QT_CONFIG(webengine_webrtc)
 #include "third_party/webrtc/modules/desktop_capture/desktop_capture_options.h"
 #include "third_party/webrtc/modules/desktop_capture/desktop_capturer.h"
 #endif
 
-#include <QtCore/qcoreapplication.h>
-
 #if defined(WEBRTC_USE_X11)
 #include <dlfcn.h>
 #include <X11/extensions/Xrandr.h>
@@ -54,7 +49,7 @@ const blink::MediaStreamDevice *findDeviceWithId(const blink::MediaStreamDevices
             return &(*iter);
         }
     }
-    return 0;
+    return nullptr;
 }
 
 // Based on chrome/browser/media/webrtc/desktop_capture_devices_util.cc:
diff --git a/src/core/media_capture_devices_dispatcher.h b/src/core/media_capture_devices_dispatcher.h
index 498b2063c..cdb84ee24 100644
--- a/src/core/media_capture_devices_dispatcher.h
+++ b/src/core/media_capture_devices_dispatcher.h
@@ -7,14 +7,12 @@
 
 #include "web_contents_adapter_client.h"
 
-#include "base/callback.h"
 #include "base/containers/circular_deque.h"
 #include "base/containers/flat_map.h"
 #include "base/memory/singleton.h"
-#include "base/observer_list.h"
 #include "chrome/browser/tab_contents/web_contents_collection.h"
 #include "content/public/browser/media_observer.h"
-#include "content/public/browser/web_contents_delegate.h"
+#include "content/public/browser/media_stream_request.h"
 
 namespace QtWebEngineCore {
 
diff --git a/src/core/net/client_cert_store_data.cpp b/src/core/net/client_cert_store_data.cpp
index 9748166b1..75c35ecc1 100644
--- a/src/core/net/client_cert_store_data.cpp
+++ b/src/core/net/client_cert_store_data.cpp
@@ -4,8 +4,6 @@
 #include "net/client_cert_store_data.h"
 
 #if QT_CONFIG(ssl)
-#include "base/logging.h"
-#include "base/memory/ptr_util.h"
 #include "net/base/net_errors.h"
 #include "net/cert/x509_certificate.h"
 #include "net/ssl/ssl_platform_key_util.h"
diff --git a/src/core/net/cookie_monster_delegate_qt.cpp b/src/core/net/cookie_monster_delegate_qt.cpp
index 1e80a0cd9..0f82a4d1f 100644
--- a/src/core/net/cookie_monster_delegate_qt.cpp
+++ b/src/core/net/cookie_monster_delegate_qt.cpp
@@ -4,10 +4,6 @@
 #include "cookie_monster_delegate_qt.h"
 
 #include "base/bind.h"
-#include "base/memory/ptr_util.h"
-#include "base/task/post_task.h"
-#include "content/public/browser/browser_task_traits.h"
-#include "content/public/browser/browser_thread.h"
 #include "net/cookies/cookie_util.h"
 #include "services/network/public/mojom/cookie_manager.mojom.h"
 
@@ -15,6 +11,8 @@
 #include "api/qwebenginecookiestore_p.h"
 #include "type_conversion.h"
 
+#include <QNetworkCookie>
+
 namespace QtWebEngineCore {
 
 class CookieChangeListener : public network::mojom::CookieChangeListener
diff --git a/src/core/net/cookie_monster_delegate_qt.h b/src/core/net/cookie_monster_delegate_qt.h
index d13203193..d84946bb9 100644
--- a/src/core/net/cookie_monster_delegate_qt.h
+++ b/src/core/net/cookie_monster_delegate_qt.h
@@ -24,7 +24,6 @@
 #endif
 #include "base/memory/ref_counted.h"
 #include "mojo/public/cpp/bindings/receiver.h"
-#include "net/cookies/cookie_change_dispatcher.h"
 #include "net/cookies/cookie_store.h"
 #include "services/network/public/mojom/cookie_manager.mojom-forward.h"
 #include "services/network/public/mojom/cookie_manager.mojom.h"
@@ -33,9 +32,9 @@
 #undef StAsH_signals
 #endif
 
-#include <QNetworkCookie>
 #include <QPointer>
 
+QT_FORWARD_DECLARE_CLASS(QNetworkCookie)
 QT_FORWARD_DECLARE_CLASS(QWebEngineCookieStore)
 
 namespace QtWebEngineCore {
@@ -77,6 +76,6 @@ public:
     void OnCookieChanged(const net::CookieChangeInfo &change);
 };
 
-}
+} // namespace QtWebEngineCore
 
 #endif // COOKIE_MONSTER_DELEGATE_QT_H
diff --git a/src/core/net/proxying_url_loader_factory_qt.cpp b/src/core/net/proxying_url_loader_factory_qt.cpp
index 216eeb214..43fba5583 100644
--- a/src/core/net/proxying_url_loader_factory_qt.cpp
+++ b/src/core/net/proxying_url_loader_factory_qt.cpp
@@ -6,15 +6,14 @@
 #include <utility>
 
 #include "base/bind.h"
-#include "base/task/post_task.h"
 #include "content/browser/web_contents/web_contents_impl.h"
-#include "content/public/browser/browser_task_traits.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/content_switches.h"
 #include "net/base/filename_util.h"
 #include "net/http/http_status_code.h"
 #include "services/network/public/cpp/cors/cors.h"
+#include "services/network/public/cpp/resource_request.h"
 #include "services/network/public/mojom/early_hints.mojom.h"
 #include "third_party/blink/public/mojom/loader/resource_load_info.mojom-shared.h"
 #include "url/url_util.h"
@@ -26,8 +25,6 @@
 #include "web_contents_adapter_client.h"
 #include "web_contents_view_qt.h"
 
-#include <QVariant>
-
 // originally based on aw_proxying_url_loader_factory.cc:
 // Copyright 2018 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
diff --git a/src/core/net/proxying_url_loader_factory_qt.h b/src/core/net/proxying_url_loader_factory_qt.h
index 58c1d4608..904a40c2d 100644
--- a/src/core/net/proxying_url_loader_factory_qt.h
+++ b/src/core/net/proxying_url_loader_factory_qt.h
@@ -4,11 +4,9 @@
 #ifndef PROXYING_URL_LOADER_FACTORY_QT_H_
 #define PROXYING_URL_LOADER_FACTORY_QT_H_
 
-#include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "mojo/public/cpp/bindings/receiver_set.h"
 #include "net/traffic_annotation/network_traffic_annotation.h"
-#include "services/network/public/cpp/resource_request.h"
 #include "services/network/public/mojom/url_loader.mojom.h"
 #include "services/network/public/mojom/url_loader_factory.mojom.h"
 
@@ -18,6 +16,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+namespace network {
+struct ResourceRequest;
+}
+
 namespace QtWebEngineCore {
 
 class ProfileAdapter;
diff --git a/src/core/net/ssl_host_state_delegate_qt.cpp b/src/core/net/ssl_host_state_delegate_qt.cpp
index 625bea678..2c64132f3 100644
--- a/src/core/net/ssl_host_state_delegate_qt.cpp
+++ b/src/core/net/ssl_host_state_delegate_qt.cpp
@@ -1,11 +1,9 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
-#include "base/callback.h"
-
 #include "ssl_host_state_delegate_qt.h"
 
-#include "type_conversion.h"
+#include "base/callback.h"
 
 namespace QtWebEngineCore {
 
diff --git a/src/core/net/ssl_host_state_delegate_qt.h b/src/core/net/ssl_host_state_delegate_qt.h
index 4ceef51d4..ff25a0587 100644
--- a/src/core/net/ssl_host_state_delegate_qt.h
+++ b/src/core/net/ssl_host_state_delegate_qt.h
@@ -5,7 +5,9 @@
 #define SSL_HOST_STATE_DELEGATE_QT_H
 
 #include "content/public/browser/ssl_host_state_delegate.h"
-#include "profile_adapter.h"
+
+#include <map>
+#include <string>
 
 namespace QtWebEngineCore {
 
diff --git a/src/core/net/webui_controller_factory_qt.cpp b/src/core/net/webui_controller_factory_qt.cpp
index 193e1795b..acb0b3fcc 100644
--- a/src/core/net/webui_controller_factory_qt.cpp
+++ b/src/core/net/webui_controller_factory_qt.cpp
@@ -24,7 +24,6 @@
 #include "content/public/common/url_utils.h"
 #include "extensions/buildflags/buildflags.h"
 #include "media/media_buildflags.h"
-#include "ppapi/buildflags/buildflags.h"
 #include "printing/buildflags/buildflags.h"
 #include "url/gurl.h"
 
diff --git a/src/core/ozone/gl_surface_qt.cpp b/src/core/ozone/gl_surface_qt.cpp
index 9b07e70e6..0e181b4c1 100644
--- a/src/core/ozone/gl_surface_qt.cpp
+++ b/src/core/ozone/gl_surface_qt.cpp
@@ -10,8 +10,6 @@
 #include "gl_surface_qt.h"
 #include "qtwebenginecoreglobal_p.h"
 
-#include "base/logging.h"
-
 #if defined(OS_WIN)
 #include "web_engine_context.h"
 #include "ozone/gl_surface_wgl_qt.h"
diff --git a/src/core/ozone/gl_surface_qt.h b/src/core/ozone/gl_surface_qt.h
index 6cba551b0..c6ea79a94 100644
--- a/src/core/ozone/gl_surface_qt.h
+++ b/src/core/ozone/gl_surface_qt.h
@@ -39,6 +39,6 @@ public:
     static std::string g_client_extensions;
 };
 
-}
+} // namespace gl
 
-#endif
+#endif // GL_SURFACE_QT_H_
diff --git a/src/core/process_main.cpp b/src/core/process_main.cpp
index 4f5561977..70c4a0970 100644
--- a/src/core/process_main.cpp
+++ b/src/core/process_main.cpp
@@ -8,7 +8,6 @@
 #include "sandbox/win/src/sandbox_types.h"
 #include "content/public/app/sandbox_helper_win.h"
 #elif defined(OS_MAC)
-#include "base/logging.h"
 #include "sandbox/mac/seatbelt_exec.h"
 #endif
 
diff --git a/src/core/renderer/content_renderer_client_qt.cpp b/src/core/renderer/content_renderer_client_qt.cpp
index f60e874cb..372c519f1 100644
--- a/src/core/renderer/content_renderer_client_qt.cpp
+++ b/src/core/renderer/content_renderer_client_qt.cpp
@@ -34,6 +34,7 @@
 #include "media/media_buildflags.h"
 #include "mojo/public/cpp/bindings/binder_map.h"
 #include "net/base/net_errors.h"
+#include "ppapi/buildflags/buildflags.h"
 #include "services/service_manager/public/cpp/connector.h"
 #include "services/service_manager/public/cpp/interface_provider.h"
 #include "third_party/blink/public/platform/web_url_error.h"
diff --git a/src/core/renderer/content_renderer_client_qt.h b/src/core/renderer/content_renderer_client_qt.h
index 522621351..8ecb0c831 100644
--- a/src/core/renderer/content_renderer_client_qt.h
+++ b/src/core/renderer/content_renderer_client_qt.h
@@ -8,14 +8,14 @@
 #include "components/spellcheck/spellcheck_buildflags.h"
 #include "services/service_manager/public/cpp/binder_registry.h"
 #include "services/service_manager/public/cpp/local_interface_provider.h"
-#include "ppapi/buildflags/buildflags.h"
-
-#if BUILDFLAG(ENABLE_PLUGINS)
-#include "third_party/blink/public/web/web_plugin_params.h"
-#endif
 
 #include <QScopedPointer>
 
+namespace blink {
+class WebPlugin;
+struct WebPluginParams;
+}
+
 namespace chrome {
 class WebRtcLoggingAgentImpl;
 }
@@ -36,10 +36,6 @@ class WebCacheImpl;
 class SpellCheck;
 #endif
 
-namespace content {
-struct WebPluginInfo;
-}
-
 namespace QtWebEngineCore {
 
 class UserResourceController;
diff --git a/src/core/renderer/extensions/extensions_renderer_client_qt.h b/src/core/renderer/extensions/extensions_renderer_client_qt.h
index 6b6c971ba..33395a615 100644
--- a/src/core/renderer/extensions/extensions_renderer_client_qt.h
+++ b/src/core/renderer/extensions/extensions_renderer_client_qt.h
@@ -5,7 +5,6 @@
 #define EXTENSIONSRENDERERCLIENTQT_H
 
 #include <memory>
-#include <string>
 
 #include "extensions/renderer/extensions_renderer_client.h"
 #include "services/service_manager/public/cpp/binder_registry.h"
@@ -20,10 +19,7 @@ class WebURL;
 }
 
 namespace content {
-class BrowserPluginDelegate;
 class RenderFrame;
-class RenderView;
-struct WebPluginInfo;
 }
 
 namespace net {
diff --git a/src/core/renderer/render_frame_observer_qt.cpp b/src/core/renderer/render_frame_observer_qt.cpp
index b1398bcb5..b8163f6eb 100644
--- a/src/core/renderer/render_frame_observer_qt.cpp
+++ b/src/core/renderer/render_frame_observer_qt.cpp
@@ -8,14 +8,17 @@
 
 #include "render_frame_observer_qt.h"
 
-#include "base/memory/ptr_util.h"
-#include "chrome/renderer/pepper/pepper_shared_memory_message_filter.h"
 #include "components/web_cache/renderer/web_cache_impl.h"
 #include "content/public/renderer/render_frame.h"
+
+#if QT_CONFIG(webengine_pepper_plugins)
+#include "base/memory/ptr_util.h"
+#include "chrome/renderer/pepper/pepper_shared_memory_message_filter.h"
 #include "content/public/renderer/renderer_ppapi_host.h"
 #include "ppapi/host/ppapi_host.h"
 
 #include "renderer/pepper/pepper_renderer_host_factory_qt.h"
+#endif
 
 namespace QtWebEngineCore {
 
diff --git a/src/core/renderer/render_frame_observer_qt.h b/src/core/renderer/render_frame_observer_qt.h
index c400c05f3..8cab3bd9a 100644
--- a/src/core/renderer/render_frame_observer_qt.h
+++ b/src/core/renderer/render_frame_observer_qt.h
@@ -5,10 +5,8 @@
 #define RENDER_FRAME_OBSERVER_QT_H
 
 #include "qtwebenginecoreglobal_p.h"
-#include "base/compiler_specific.h"
 #include "content/public/renderer/render_frame_observer.h"
 #include "content/public/renderer/render_frame_observer_tracker.h"
-#include "ppapi/buildflags/buildflags.h"
 #include "services/service_manager/public/cpp/binder_registry.h"
 #include "third_party/blink/public/common/associated_interfaces/associated_interface_registry.h"
 
diff --git a/src/core/user_notification_controller.cpp b/src/core/user_notification_controller.cpp
index b7782fe1e..9c1122cca 100644
--- a/src/core/user_notification_controller.cpp
+++ b/src/core/user_notification_controller.cpp
@@ -5,8 +5,6 @@
 
 #include "type_conversion.h"
 
-#include "base/callback.h"
-#include "content/public/browser/notification_event_dispatcher.h"
 #include "third_party/blink/public/mojom/notifications/notification.mojom-shared.h"
 #include "third_party/blink/public/common/notifications/notification_resources.h"
 #include "third_party/blink/public/common/notifications/platform_notification_data.h"
diff --git a/src/core/web_contents_adapter.cpp b/src/core/web_contents_adapter.cpp
index 8385a7b0e..3521bb547 100644
--- a/src/core/web_contents_adapter.cpp
+++ b/src/core/web_contents_adapter.cpp
@@ -12,6 +12,7 @@
 #include "download_manager_delegate_qt.h"
 #include "favicon_driver_qt.h"
 #include "favicon_service_factory_qt.h"
+#include "find_text_helper.h"
 #include "media_capture_devices_dispatcher.h"
 #include "profile_adapter.h"
 #include "profile_qt.h"
diff --git a/src/core/web_contents_delegate_qt.cpp b/src/core/web_contents_delegate_qt.cpp
index f68310b75..f7c1ea164 100644
--- a/src/core/web_contents_delegate_qt.cpp
+++ b/src/core/web_contents_delegate_qt.cpp
@@ -7,13 +7,16 @@
 
 #include "web_contents_delegate_qt.h"
 
-#include "profile_adapter.h"
+#include "certificate_error_controller.h"
 #include "color_chooser_controller.h"
 #include "color_chooser_qt.h"
 #include "custom_handlers/protocol_handler_registry_factory.h"
 #include "custom_handlers/register_protocol_handler_request_controller_impl.h"
 #include "file_picker_controller.h"
+#include "find_text_helper.h"
+#include "javascript_dialog_manager_qt.h"
 #include "media_capture_devices_dispatcher.h"
+#include "profile_adapter.h"
 #include "profile_qt.h"
 #include "qwebengineloadinginfo.h"
 #include "qwebengineregisterprotocolhandlerrequest.h"
@@ -31,11 +34,11 @@
 #include "components/custom_handlers/protocol_handler_registry.h"
 #include "components/web_cache/browser/web_cache_manager.h"
 #include "content/browser/renderer_host/render_frame_host_impl.h"
-#include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/file_select_listener.h"
 #include "content/public/browser/invalidate_type.h"
+#include "content/public/browser/media_stream_request.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/navigation_handle.h"
 #include "content/public/browser/render_view_host.h"
diff --git a/src/core/web_contents_delegate_qt.h b/src/core/web_contents_delegate_qt.h
index 3a71d3bcb..7157b5130 100644
--- a/src/core/web_contents_delegate_qt.h
+++ b/src/core/web_contents_delegate_qt.h
@@ -5,18 +5,13 @@
 #define WEB_CONTENTS_DELEGATE_QT_H
 
 #include "content/browser/renderer_host/frame_tree_node.h"
-#include "content/public/browser/media_capture_devices.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "third_party/skia/include/core/SkColor.h"
 
-#include "base/callback.h"
+#include "web_contents_adapter_client.h"
 
-#include "color_chooser_controller.h"
-#include "find_text_helper.h"
-#include "javascript_dialog_manager_qt.h"
 #include <QtCore/qlist.h>
-#include <QWebEngineCertificateError>
 
 namespace blink {
     namespace web_pref {
@@ -25,15 +20,15 @@ namespace blink {
 }
 
 namespace content {
-    class ColorChooser;
-    class SiteInstance;
-    class JavaScriptDialogManager;
-    class WebContents;
-    struct ColorSuggestion;
+class ColorChooser;
+class JavaScriptDialogManager;
+class WebContents;
+struct MediaStreamRequest;
 }
 
 namespace QtWebEngineCore {
 
+class FindTextHelper;
 class WebContentsAdapter;
 class WebContentsAdapterClient;
 class WebEngineSettings;
diff --git a/src/core/web_engine_context.cpp b/src/core/web_engine_context.cpp
index b89579100..d81e1b86b 100644
--- a/src/core/web_engine_context.cpp
+++ b/src/core/web_engine_context.cpp
@@ -59,7 +59,6 @@
 #include "media/base/media_switches.h"
 #include "mojo/core/embedder/embedder.h"
 #include "net/base/port_util.h"
-#include "ppapi/buildflags/buildflags.h"
 #include "sandbox/policy/switches.h"
 #include "services/network/public/cpp/features.h"
 #include "services/network/public/cpp/network_switches.h"
diff --git a/src/webenginequick/api/qquickwebengineprofile_p.h b/src/webenginequick/api/qquickwebengineprofile_p.h
index 4b3f63907..e7d72af17 100644
--- a/src/webenginequick/api/qquickwebengineprofile_p.h
+++ b/src/webenginequick/api/qquickwebengineprofile_p.h
@@ -55,7 +55,6 @@ public:
     void showNotification(QSharedPointer<QtWebEngineCore::UserNotificationController> &controller) override;
 
 private:
-    friend class QQuickWebEngineView;
     QQuickWebEngineProfile *q_ptr;
     QScopedPointer<QQuickWebEngineSettings> m_settings;
     QPointer<QtWebEngineCore::ProfileAdapter> m_profileAdapter;
diff --git a/src/webenginequick/ui_delegates_manager.h b/src/webenginequick/ui_delegates_manager.h
index 25e99a64e..7e05cf324 100644
--- a/src/webenginequick/ui_delegates_manager.h
+++ b/src/webenginequick/ui_delegates_manager.h
@@ -4,7 +4,8 @@
 #ifndef UI_DELEGATES_MANAGER_H
 #define UI_DELEGATES_MANAGER_H
 
-#include <QtCore/qcoreapplication.h>
+#include <QtCore/qcoreapplication.h> // Q_DECLARE_TR_FUNCTIONS
+#include <QtCore/qobject.h>
 #include <QtCore/qpoint.h>
 #include <QtCore/qscopedpointer.h>
 #include <QtCore/qsharedpointer.h>
@@ -34,6 +35,7 @@
     QQmlComponent *COMPONENT##Component
 
 QT_BEGIN_NAMESPACE
+class QEvent;
 class QQmlComponent;
 class QQmlContext;
 class QQmlEngine;
diff --git a/src/webenginewidgets/api/qwebengineview.h b/src/webenginewidgets/api/qwebengineview.h
index 24dbe6b13..f93d61b12 100644
--- a/src/webenginewidgets/api/qwebengineview.h
+++ b/src/webenginewidgets/api/qwebengineview.h
@@ -138,8 +138,6 @@ private:
     QScopedPointer<QWebEngineViewPrivate> d_ptr;
 
     friend class QtWebEngineWidgetUI::AutofillPopupWidget;
-    friend class QWebEnginePage;
-    friend class QWebEnginePagePrivate;
 #if QT_CONFIG(accessibility)
     friend class QWebEngineViewAccessible;
 #endif