[Mac] Revert diagnostics for content popup bug.

chrome/browser/renderer_host/render_widget_host_view_mac.h

Index: chrome/browser/renderer_host/render_widget_host_view_mac.h
diff --git a/chrome/browser/renderer_host/render_widget_host_view_mac.h b/chrome/browser/renderer_host/render_widget_host_view_mac.h
index e38071beeb85beae767a8d3b3048c0c2011f7db0..3dc07b25ad1447bca6e2beac1f7adb4a2052bb74 100644
--- a/chrome/browser/renderer_host/render_widget_host_view_mac.h
+++ b/chrome/browser/renderer_host/render_widget_host_view_mac.h
@@ -115,10 +115,6 @@ class RenderWidgetHostViewMac : public RenderWidgetHostView {
 
   void set_parent_view(BaseView* parent_view) { parent_view_ = parent_view; }
 
-  // Used only to diagnose the crash in http://crbug.com/31716
-  // TODO(pamg): Remove when no longer needed.
-  void clear_cocoa_view() { cocoa_view_ = nil; }
-
   // These member variables should be private, but the associated ObjC class
   // needs access to them and can't be made a friend.