Make sure examples are always built

When building against Qt 5 release binaries, QT_BUILD_PARTS does not include
examples. However we want to unconditionally build examples, until we become
part of the Qt 5 module set.

(cherry picked from commit f2fb23f2

)

Change-Id: I6239c3f9280c50f5418947f711924be59265c4ce
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

qtwebengine.pro

+load(qt_build_config)
+
+# As long as we are a module separate from the rest of Qt, we want to unconditionally build examples.
+# Once part of Qt 5, this should be removed and we should respect the Qt wide configuration.
+QTWEBENGINE_BUILD_PARTS = $$QT_BUILD_PARTS
+QTWEBENGINE_BUILD_PARTS *= examples
+
 load(qt_parts)