Make browser windows override_redirect when dragging tabs.

ui/aura/window_tree_host_x11.h

Index: ui/aura/window_tree_host_x11.h
diff --git a/ui/aura/window_tree_host_x11.h b/ui/aura/window_tree_host_x11.h
index bc994a7eb877df92d5faa1d49221ea4f432e7da7..af14ca67ed787042c2d3754b5d479b5348e8af3f 100644
--- a/ui/aura/window_tree_host_x11.h
+++ b/ui/aura/window_tree_host_x11.h
@@ -49,6 +49,7 @@ class AURA_EXPORT WindowTreeHostX11 : public WindowTreeHost,
   gfx::Point GetLocationOnNativeScreen() const override;
   void SetCapture() override;
   void ReleaseCapture() override;
+  void RemapWindow() override;
   void SetCursorNative(gfx::NativeCursor cursor_type) override;
   void MoveCursorToNative(const gfx::Point& location) override;
   void OnCursorVisibilityChangedNative(bool show) override;