Make sure manifest specified shortcut for Extension Command can not override the built-in shortcuts.

chrome/browser/extensions/extension_keybinding_apitest.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 "chrome/browser/extensions/active_tab_permission_granter.h"
 #include "chrome/browser/extensions/browser_action_test_util.h"
 #include "chrome/browser/extensions/extension_action.h"
 #include "chrome/browser/extensions/extension_action_manager.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/browser/extensions/tab_helper.h"
@@ skipping 177 matching lines @@
 }
 
 // This test validates that the getAll query API function returns registered
 // commands as well as synthesized ones and that inactive commands (like the
 // synthesized ones are in nature) have no shortcuts.
 IN_PROC_BROWSER_TEST_F(CommandsApiTest, SynthesizedCommand) {
   ASSERT_TRUE(test_server()->Start());
   ASSERT_TRUE(RunExtensionTest("keybinding/synthesized")) << message_;
 }
 
+// This test validates that an extension cannot request a shortcut that is
+// already in use by Chrome.
+#if !defined(OS_MACOSX)
+IN_PROC_BROWSER_TEST_F(CommandsApiTest, DontOverwriteSystemShortcuts) {
+  ASSERT_TRUE(test_server()->Start());
+  ASSERT_TRUE(RunExtensionTest("keybinding/dont_overwrite_system")) << message_;
+
+  ui_test_utils::NavigateToURL(browser(),
+      test_server()->GetURL("files/extensions/test_file.txt"));
+
+  WebContents* tab = browser()->tab_strip_model()->GetActiveWebContents();
+  ASSERT_TRUE(tab);
+
+  // Activate the shortcut (Ctrl+Shift+F) to make page blue.
+  ASSERT_TRUE(ui_test_utils::SendKeyPressSync(
+      browser(), ui::VKEY_F, true, true, false, false));
+
+  bool result = false;
+  ASSERT_TRUE(content::ExecuteScriptAndExtractBool(
+      tab,
+      "setInterval(function() {"
+      "  if (document.body.bgColor == 'blue') {"
+      "    window.domAutomationController.send(true)}}, 100)",
+      &result));
+  ASSERT_TRUE(result);
+
+  // Activate the shortcut (Ctrl+F) to make page red (should not work).
+  ASSERT_TRUE(ui_test_utils::SendKeyPressSync(
+      browser(), ui::VKEY_F, true, false, false, false));
+
+  // The page should still be blue.
+  result = false;
+  ASSERT_TRUE(content::ExecuteScriptAndExtractBool(
+      tab,
+      "setInterval(function() {"
+      "  if (document.body.bgColor == 'blue') {"
+      "    window.domAutomationController.send(true)}}, 100)",
+      &result));
+  ASSERT_TRUE(result);
+}
+#endif  // !defined(OS_MACOSX)
+
 }  // extensions