Change browser/page action default icon defined in manifest to support hidpi.

chrome/common/extensions/manifest_tests/extension_manifests_pageaction_unittest.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/common/extensions/manifest_tests/extension_manifest_test.h"
 
 #include "chrome/common/extensions/extension_action.h"
 #include "chrome/common/extensions/extension_manifest_constants.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace errors = extension_manifest_errors;
 
 TEST_F(ExtensionManifestTest, PageActionManifestVersion2) {
   scoped_refptr<extensions::Extension> extension(
       LoadAndExpectSuccess("page_action_manifest_version_2.json"));
   ASSERT_TRUE(extension.get());
   ASSERT_TRUE(extension->page_action());
 
   EXPECT_EQ("", extension->page_action()->id());
-  EXPECT_TRUE(extension->page_action()->default_icon_path().empty());
+  EXPECT_FALSE(extension->page_action()->default_icon());
   EXPECT_EQ("", extension->page_action()->GetTitle(
       ExtensionAction::kDefaultTabId));
   EXPECT_FALSE(extension->page_action()->HasPopup(
       ExtensionAction::kDefaultTabId));
 
   LoadAndExpectError("page_action_manifest_version_2b.json",
                      errors::kInvalidPageActionPopup);
 }