Work around a bug in KWin where the window shape doesn't get

chrome/browser/gtk/browser_window_gtk.cc

Index: chrome/browser/gtk/browser_window_gtk.cc
diff --git a/chrome/browser/gtk/browser_window_gtk.cc b/chrome/browser/gtk/browser_window_gtk.cc
index 57d18c628aa45e11a8f9ffd08b33e3709899308b..b8b5fd64d067bbf01d4e7e0fbdee2b2f8517bae4 100644
--- a/chrome/browser/gtk/browser_window_gtk.cc
+++ b/chrome/browser/gtk/browser_window_gtk.cc
@@ -1123,8 +1123,12 @@ void BrowserWindowGtk::UpdateWindowShape(int width, int height) {
     gtk_alignment_set_padding(GTK_ALIGNMENT(window_container_), 1,
         kFrameBorderThickness, kFrameBorderThickness, kFrameBorderThickness);
   } else {
-    // Disable rounded corners.
-    gdk_window_shape_combine_region(GTK_WIDGET(window_)->window, NULL, 0, 0);
+    // Disable rounded corners.  Simply passing in a NULL region doesn't
+    // seem to work on KWin, so manually set the shape to the whole window.
+    GdkRectangle rect = { 0, 0, width, height };
+    GdkRegion* mask = gdk_region_rectangle(&rect);
+    gdk_window_shape_combine_region(GTK_WIDGET(window_)->window, mask, 0, 0);
+    gdk_region_destroy(mask);
     gtk_alignment_set_padding(GTK_ALIGNMENT(window_container_), 0, 0, 0, 0);
   }
 }