Remove window flags WindowOkButtonHint, WindowCancelButtonHint.

They were duplicating other enumeration values
(WindowTransparentForInput, WindowOverridesSystemGestures) and were
only supported on Windows CE.

Task-number: QTBUG-42897
Task-number: QTBUG-51673
Change-Id: I993a933ee2a3dc8a0ebd7ba6aef80b456f50a657
Reviewed-by: Lars Knoll <lars.knoll@theqtcompany.com>

src/corelib/global/qnamespace.h

@@ -301,12 +301,7 @@ public:
         MacWindowToolBarButtonHint = 0x10000000,
         BypassGraphicsProxyWidget = 0x20000000,
         NoDropShadowWindowHint = 0x40000000,
-        WindowFullscreenButtonHint = 0x80000000,
-
-        // The following enums have overlapping values with other enums.
-        // This was not intentional, but it's too late to change now.
-        WindowOkButtonHint = 0x00080000, // WindowTransparentForInput
-        WindowCancelButtonHint = 0x00100000 // WindowOverridesSystemGestures
+        WindowFullscreenButtonHint = 0x80000000
     };
 
     Q_DECLARE_FLAGS(WindowFlags, WindowType)

src/corelib/global/qnamespace.qdoc

@@ -2203,12 +2203,6 @@
            the bottom.  This window hint is currently not implemented
            for OS X.
 
-    \value WindowOkButtonHint Adds an OK button to the window decoration of a dialog.
-           Only supported for Windows CE.
-
-    \value WindowCancelButtonHint Adds a Cancel button to the window decoration of a dialog.
-           Only supported for Windows CE.
-
     \value WindowTransparentForInput Informs the window system that this window
            is used only for output (displaying something) and does not take input.
            Therefore input events should pass through as if it wasn't there.

tests/manual/diaglib/qwindowdump.cpp

@@ -113,8 +113,6 @@ void formatWindowFlags(QTextStream &str, const Qt::WindowFlags flags)
     debugFlag(str, flags, Qt::WindowStaysOnBottomHint)
     debugFlag(str, flags, Qt::MacWindowToolBarButtonHint)
     debugFlag(str, flags, Qt::BypassGraphicsProxyWidget)
-    debugFlag(str, flags, Qt::WindowOkButtonHint)
-    debugFlag(str, flags, Qt::WindowCancelButtonHint)
 }
 
 #if QT_VERSION > 0x050000