Add --draw-view-bounds-rects to draw bounds rects for all views.

ui/views/views_switches.cc

Index: ui/views/views_switches.cc
diff --git a/ui/views/views_switches.cc b/ui/views/views_switches.cc
index 9fa09fc3c119f9da2f558206fffe87e73fe9dd9e..79fe2574aec3a54d270d5d6d8924241e58550a6d 100644
--- a/ui/views/views_switches.cc
+++ b/ui/views/views_switches.cc
@@ -17,6 +17,9 @@ namespace switches {
 const char kDisableViewsRectBasedTargeting[] =
     "disable-views-rect-based-targeting";
 
+// Draws a semitransparent rect to indicate the bounds of each view.
+const char kDrawViewBoundsRects[] = "draw-view-bounds-rects";
+
 bool IsRectBasedTargetingEnabled() {
 #if defined(OS_CHROMEOS) || defined(OS_WIN) || defined(OS_LINUX)
   return !base::CommandLine::ForCurrentProcess()->HasSwitch(