Merge 284026 "Add app.window.alphaEnabled() and onAlphaEnabledCh..."

ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc

Index: ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
===================================================================
--- ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc	(revision 285043)
+++ ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc	(working copy)
@@ -365,7 +365,7 @@
 }
 
 bool DesktopWindowTreeHostWin::ShouldUseNativeFrame() const {
-  return ui::win::IsAeroGlassEnabled();
+  return IsTranslucentWindowOpacitySupported();
 }
 
 bool DesktopWindowTreeHostWin::ShouldWindowContentsBeTransparent() const {
@@ -427,6 +427,10 @@
   return pending_close_;
 }
 
+bool DesktopWindowTreeHostWin::IsTranslucentWindowOpacitySupported() const {
+  return ui::win::IsAeroGlassEnabled();
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // DesktopWindowTreeHostWin, WindowTreeHost implementation: