Split QPlatformWindow::isEmbedded into isAncestorOf to separate concerns

The function was doing two things, both checking window ancestry and
whether or the window was a direct child of non-Qt window. The former
has now been split of in a QPlatformWindow::isAncestorOf(), which
simplifies the code in e.g. QApplicationPrivate::isWindowBlocked().

Change-Id: I259a190e03ef8def23356005474eeeee74c9ae89
Reviewed-by: Miikka Heikkinen <miikka.heikkinen@qt.io>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

1 files changed, 7 insertions, 2 deletions

diff --git a/src/gui/kernel/qwindow.cpp b/src/gui/kernel/qwindow.cpp
index 93edfe6331..5a27b19101 100644
--- a/src/gui/kernel/qwindow.cpp
+++ b/src/gui/kernel/qwindow.cpp
@@ -1300,8 +1300,13 @@ bool QWindow::isAncestorOf(const QWindow *child, AncestorMode mode) const
     if (child->parent() == this || (mode == IncludeTransients && child->transientParent() == this))
         return true;
 
-    if (child->parent(mode) && isAncestorOf(child->parent(mode), mode))
-        return true;
+    if (QWindow *parent = child->parent(mode)) {
+        if (isAncestorOf(parent, mode))
+            return true;
+    } else if (handle() && child->handle()) {
+        if (handle()->isAncestorOf(child->handle()))
+            return true;
+    }
 
     return false;
 }