[Cocoa] Make TabContentsContainerView more testable for interactive_ui_tests.

chrome/test/base/interactive_test_utils_mac.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/test/base/interactive_test_utils.h"
 
 #include <Carbon/Carbon.h>
 #import <Cocoa/Cocoa.h>
 
 #include "base/bind.h"
@@ skipping 36 matching lines @@
   NSWindow* window = browser->window()->GetNativeWindow();
   DCHECK(window);
   NSView* view = view_id_util::GetView(window, vid);
   if (!view)
     return false;
 
   NSResponder* firstResponder = [window firstResponder];
   if (firstResponder == static_cast<NSResponder*>(view))
     return true;
 
+  // Handle special case for VIEW_ID_TAB_CONTAINER.  The tab container NSView
+  // always transfers first responder status to its subview, so test whether
+  // |firstResponder| is a descendant.
+  if (vid == VIEW_ID_TAB_CONTAINER &&
+      [firstResponder isKindOfClass:[NSView class]])
+    return [static_cast<NSView*>(firstResponder) isDescendantOf:view];
+
   // Handle the special case of focusing a TextField.
   if ([firstResponder isKindOfClass:[NSTextView class]]) {
     NSView* delegate = static_cast<NSView*>([(NSTextView*)firstResponder
                                                           delegate]);
     if (delegate == view)
       return true;
   }
 
   return false;
 }
@@ skipping 27 matching lines @@
   // Make sure an unbundled program can get the input focus.
   ProcessSerialNumber psn = { 0, kCurrentProcess };
   TransformProcessType(&psn,kProcessTransformToForegroundApplication);
   SetFrontProcess(&psn);
 
   [window makeKeyAndOrderFront:nil];
   return true;
 }
 
 }  // namespace ui_test_utils