Insert diagnostics in an attempt to track down a crash in popup menus...

chrome/browser/renderer_host/render_widget_host_view_mac.mm

Index: chrome/browser/renderer_host/render_widget_host_view_mac.mm
===================================================================
--- chrome/browser/renderer_host/render_widget_host_view_mac.mm	(revision 36540)
+++ chrome/browser/renderer_host/render_widget_host_view_mac.mm	(working copy)
@@ -419,8 +419,12 @@
                                        [menu_runner indexOfSelectedItem],
                                        position, view_rect);
 
+  // CHECK()s inserted to diagnose the crash in http://crbug.com/31716
+  // TODO(pamg): Remove when no longer needed.
+  CHECK(render_widget_host_);
   if ([menu_runner menuItemWasChosen]) {
     // Simulate a menu selection event.
+    CHECK(cocoa_view_);
     const WebMouseEvent& mouse_event =
         WebInputEventFactory::mouseEvent(event, cocoa_view_);
     render_widget_host_->ForwardMouseEvent(mouse_event);
@@ -577,6 +581,13 @@
   return self;
 }
 
+// Used only to diagnose the crash in http://crbug.com/31716
+// TODO(pamg): Remove when no longer needed.
+- (void)dealloc {
+  renderWidgetHostView_->clear_cocoa_view();
+  [super dealloc];
+}
+
 - (void)setCanBeKeyView:(BOOL)can {
   canBeKeyView_ = can;
 }