Split ExtensionSystem interface from ExtensionSystemImpl implementation, part 1.

chrome/browser/extensions/options_page_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/extension_browsertest.h"
 #include "chrome/browser/extensions/extension_service.h"
-#include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/test/browser_test_utils.h"
+#include "extensions/browser/extension_system.h"
 #include "extensions/common/extension.h"
 
 using extensions::Extension;
 
 // Used to simulate a click on the first element named 'Options'.
 static const char kScriptClickOptionButton[] =
     "(function() { "
     "  var button = document.querySelector('.options-link');"
     "  button.click();"
     "})();";
@@ skipping 23 matching lines @@
   EXPECT_TRUE(content::ExecuteScriptInFrame(
       tab_strip->GetActiveWebContents(),
       "//iframe[starts-with(@src, 'chrome://extension')]",
       kScriptClickOptionButton));
   observer.Wait();
   EXPECT_EQ(2, tab_strip->count());
 
   EXPECT_EQ(extension->GetResourceURL("options.html"),
             tab_strip->GetWebContentsAt(1)->GetURL());
 }