CMake: Fix X11 and xkb library usage in the platform projects

This is a prerequisite for building the bundled 3rd party libraries.

Because the feature evaluation will be moved into src/CMakeLists.txt,
some of the X11 packages were found in the src dir, and then a second
time inside the x11-related projects.
These qt_find_package calls in the x11 related projects tried to
promote the imported targets to global, which failed, because they were
created in a different directory scope.

To avoid this, the special case qt_find_package calls are removed from
the nested projects.

Also, fix the mapping of some of the x11 libraries to be correct
- xkbcommon_x11 was incorrectly mapped to XKB::XKB instead of the
  xkb common x11 library
- xlib was mapped to xcb, whereas X11 is the correct CMake target

Change-Id: I30781b2ecbdd478c98419b14baa0492037e49c61
Reviewed-by: Leander Beernaert <leander.beernaert@qt.io>
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 7 insertions, 24 deletions

diff --git a/src/plugins/platforms/xcb/CMakeLists.txt b/src/plugins/platforms/xcb/CMakeLists.txt
index d422d69891..a7cb58ba29 100644
--- a/src/plugins/platforms/xcb/CMakeLists.txt
+++ b/src/plugins/platforms/xcb/CMakeLists.txt
@@ -1,27 +1,5 @@
 # Generated from xcb.pro.
 
-# begin special case:
-qt_find_package(X11_XCB
-    PROVIDED_TARGETS
-        X11::XCB
-)
-qt_find_package(X11
-    PROVIDED_TARGETS
-        X11::X11
-)
-qt_find_package(XCB)
-qt_find_package(XKB)
-qt_find_package(PkgConfig)
-qt_find_package(WrapFreetype)
-qt_find_package(GLIB2
-    PROVIDED_TARGETS
-        GLIB2::GLIB2
-)
-qt_find_package(XRender PROVIDED_TARGETS PkgConfig::XRender)
-qt_find_package(XKB_COMMON_X11 PROVIDED_TARGETS PkgConfig::XKB_COMMON_X11)
-
-# end special case:
-
 #####################################################################
 ## XcbQpa Module:
 #####################################################################
@@ -61,6 +39,7 @@ qt_add_module(XcbQpa
     INCLUDE_DIRECTORIES
         gl_integrations
     PUBLIC_LIBRARIES
+        PkgConfig::XKB_COMMON_X11
         Qt::CorePrivate
         Qt::EdidSupportPrivate
         Qt::FontDatabaseSupportPrivate
@@ -68,7 +47,6 @@ qt_add_module(XcbQpa
         Qt::ServiceSupportPrivate
         Qt::ThemeSupportPrivate
         Qt::XkbCommonSupportPrivate
-        PkgConfig::XKB_COMMON_X11 # special case
         XCB::ICCCM
         XCB::IMAGE
         XCB::KEYSYMS
@@ -120,7 +98,12 @@ qt_extend_target(XcbQpa CONDITION QT_FEATURE_draganddrop
 qt_extend_target(XcbQpa CONDITION QT_FEATURE_xcb_xlib
     PUBLIC_LIBRARIES
         X11::XCB
-        X11::X11 # special case
+        # special case begin
+        # 'QMAKE_USE += xcb_xlib' in qmake implies also += xlib (aka X11)
+        # due to "use": "xcb xlib" in src/gui/configure.json.
+        # That's not yet handled by the conversion scripts unfortunately.
+        X11::X11
+        # special case end
 )
 
 qt_extend_target(XcbQpa CONDITION QT_FEATURE_xcb_sm