Handle initial NavigationEntries

Chromium introduced the Initial NavigationEntry that meant to
represent the initial empty document at FrameTree creation time.
It is just a placeholder entry put in the list of NavigationEntries
that gets replaced on the next navigation.
A side effect of this is that we have an extra entry in the list before
we load any page.

This change also reverts the history related tests modified by
106 Adaptations that introduced this behavior.

Fixes: QTBUG-117489
Pick-to: 6.5 6.6
Change-Id: I2738591b681082792544bd884f8ecec54ce9d72d
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

1 files changed, 22 insertions, 4 deletions

diff --git a/src/core/web_contents_adapter.cpp b/src/core/web_contents_adapter.cpp
index 31a3ab93c..91a939bd2 100644
--- a/src/core/web_contents_adapter.cpp
+++ b/src/core/web_contents_adapter.cpp
@@ -210,10 +210,28 @@ static std::unique_ptr<content::WebContents> createBlankWebContents(WebContentsA
     return webContents;
 }
 
+static int navigationListSize(content::NavigationController &controller) {
+    // If we're currently on the initial NavigationEntry, no navigation has
+    // committed, so the initial NavigationEntry should not be part of the
+    // "Navigation List", and we should return 0 as the navigation list size.
+    if (controller.GetLastCommittedEntry()->IsInitialEntry())
+        return 0;
+    return controller.GetEntryCount();
+}
+
+static int navigationListCurrentIndex(content::NavigationController &controller) {
+    // If we're currently on the initial NavigationEntry, no navigation has
+    // committed, so the initial NavigationEntry should not be part of the
+    // "Navigation List", and we should return -1 as the current index.
+    if (controller.GetLastCommittedEntry()->IsInitialEntry())
+        return -1;
+    return controller.GetCurrentEntryIndex();
+}
+
 static void serializeNavigationHistory(content::NavigationController &controller, QDataStream &output)
 {
-    const int currentIndex = controller.GetCurrentEntryIndex();
-    const int count = controller.GetEntryCount();
+    const int currentIndex = navigationListCurrentIndex(controller);
+    const int count = navigationListSize(controller);
     const int pendingIndex = controller.GetPendingEntryIndex();
 
     output << kHistoryStreamVersion;
@@ -910,13 +928,13 @@ void WebContentsAdapter::navigateToOffset(int offset)
 int WebContentsAdapter::navigationEntryCount()
 {
     CHECK_INITIALIZED(0);
-    return m_webContents->GetController().GetEntryCount();
+    return navigationListSize(m_webContents->GetController());
 }
 
 int WebContentsAdapter::currentNavigationEntryIndex()
 {
     CHECK_INITIALIZED(0);
-    return m_webContents->GetController().GetCurrentEntryIndex();
+    return navigationListCurrentIndex(m_webContents->GetController());
 }
 
 QUrl WebContentsAdapter::getNavigationEntryOriginalUrl(int index)