P2.1a.

chrome/browser/cocoa/hover_close_button.mm

Index: chrome/browser/cocoa/hover_close_button.mm
diff --git a/chrome/browser/cocoa/hover_close_button.mm b/chrome/browser/cocoa/hover_close_button.mm
index 10c6e46416b55780273d2f7506e8d2b06be86faf..dd3ec510d41c35cc3986e496d0baf286d466e4e8 100644
--- a/chrome/browser/cocoa/hover_close_button.mm
+++ b/chrome/browser/cocoa/hover_close_button.mm
@@ -6,6 +6,7 @@
 
 #include "app/l10n_util.h"
 #include "base/nsimage_cache_mac.h"
+#import "chrome/browser/cocoa/tab_controller.h"
 #include "grit/generated_resources.h"
 
 namespace  {
@@ -56,6 +57,12 @@ const NSString* kPressedImageString = @"close_bar_p.pdf";
 }
 
 - (void)mouseDown:(NSEvent*)theEvent {
+  // controller_ is only set for close buttons in the tab strip.
+  if (controller_ && ![controller_ closeButtonActive]) {
+    [[controller_ view] mouseDown:theEvent];
+    return;
+  }
+
   // The hover button needs to hold onto itself here for a bit.  Otherwise,
   // it can be freed while |super mouseDown:| is in it's loop, and the
   // |checkImageState| call will crash.