[Cocoa] Make TabContentsContainerView more testable for interactive_ui_tests.

chrome/browser/ui/browser_focus_uitest.cc

 // 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 "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/format_macros.h"
 #include "base/message_loop/message_loop.h"
 #include "base/path_service.h"
 #include "base/strings/stringprintf.h"
@@ skipping 79 matching lines @@
 #elif defined(OS_WIN)
     // This loop times out on Windows XP with no output. http://crbug.com/376635
     if (base::win::GetVersion() < base::win::VERSION_VISTA)
       return;
 #endif
 
     // Loop through the focus chain twice for good measure.
     for (size_t i = 0; i < 2; ++i) {
       SCOPED_TRACE(base::StringPrintf("focus outer loop: %" PRIuS, i));
       ASSERT_TRUE(IsViewFocused(VIEW_ID_OMNIBOX));
+
       // Mac requires an extra Tab key press to traverse the app menu button
-      // iff "Full Keyboard Access" is enabled. This test code should probably
-      // check the setting via NSApplication's isFullKeyboardAccessEnabled.
+      // iff "Full Keyboard Access" is enabled. In reverse, four Tab key presses
+      // are required to traverse the back/forward buttons and the tab strip.
+#if defined(OS_MACOSX)
+      if (ui_controls::IsFullKeyboardAccessEnabled()) {
+        ASSERT_TRUE(ui_test_utils::SendKeyPressSync(
+            browser(), key, false, reverse, false, false));
+        if (reverse) {
+          for (int j = 0; j < 3; ++j) {
+            ASSERT_TRUE(ui_test_utils::SendKeyPressSync(
+                browser(), key, false, reverse, false, false));
+          }
+        }
+      }
+#endif
 
       for (size_t j = 0; j < arraysize(kExpectedIDs); ++j) {
         SCOPED_TRACE(base::StringPrintf("focus inner loop %" PRIuS, j));
         const size_t index = reverse ? arraysize(kExpectedIDs) - 1 - j : j;
         // The details are the node's editable state, i.e. true for "textEdit".
         bool is_editable_node = index == 0;
 
         // Press Tab (or Shift+Tab) and check the focused element id.
         ASSERT_TRUE(ui_test_utils::SendKeyPressAndWaitWithDetails(
             browser(), key, false, reverse, false, false,
@@ skipping 566 matching lines @@
         content::NOTIFICATION_NAV_ENTRY_COMMITTED,
         content::NotificationService::AllSources());
     chrome::GoForward(browser(), CURRENT_TAB);
     forward_nav_observer.Wait();
   }
 
   EXPECT_FALSE(IsViewFocused(VIEW_ID_OMNIBOX));
 }
 
 }  // namespace