It turns out I had the sense of the GetLocalBounds bool wrong everywhere, so ...

chrome/browser/ui/views/info_bubble.cc

Index: chrome/browser/ui/views/info_bubble.cc
===================================================================
--- chrome/browser/ui/views/info_bubble.cc	(revision 74228)
+++ chrome/browser/ui/views/info_bubble.cc	(working copy)
@@ -113,7 +113,7 @@
   paint.setStyle(SkPaint::kFill_Style);
   paint.setColor(InfoBubble::kBackgroundColor);
   gfx::Path path;
-  gfx::Rect bounds(GetLocalBounds());
+  gfx::Rect bounds(GetContentsBounds());
   SkRect rect;
   rect.set(SkIntToScalar(bounds.x()), SkIntToScalar(bounds.y()),
            SkIntToScalar(bounds.right()), SkIntToScalar(bounds.bottom()));