[Mac] Address buggy permission bubble behaviour on dismissal via ESC.

chrome/browser/ui/cocoa/website_settings/permission_bubble_controller.mm

Index: chrome/browser/ui/cocoa/website_settings/permission_bubble_controller.mm
diff --git a/chrome/browser/ui/cocoa/website_settings/permission_bubble_controller.mm b/chrome/browser/ui/cocoa/website_settings/permission_bubble_controller.mm
index bc593c1bfb61cda12898ea55b013bb008f06be50..655519a79266f3ad9e2b564323651ae18cfcfcee 100644
--- a/chrome/browser/ui/cocoa/website_settings/permission_bubble_controller.mm
+++ b/chrome/browser/ui/cocoa/website_settings/permission_bubble_controller.mm
@@ -225,6 +225,9 @@ const NSInteger kFullscreenLeftOffset = 40;
 // vertical center of |viewB|.
 + (void)alignCenterOf:(NSView*)viewA verticallyToCenterOf:(NSView*)viewB;
 
+// BaseBubbleController override.
+- (IBAction)cancel:(id)sender;
+
 @end
 
 @implementation PermissionBubbleController
@@ -660,4 +663,11 @@ const NSInteger kFullscreenLeftOffset = 40;
   [viewA setFrameOrigin:frameA.origin];
 }
 
+- (IBAction)cancel:(id)sender {
+  // This is triggered by ESC when the bubble has focus.
+  DCHECK(delegate_);
+  delegate_->Closing();
+  [super cancel:sender];
+}
+
 @end  // implementation PermissionBubbleController