Avoid parsing the webstore base url so much.

extensions/common/extension_urls.h

 // Copyright 2013 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.
 
 #ifndef EXTENSIONS_COMMON_EXTENSION_URLS_H_
 #define EXTENSIONS_COMMON_EXTENSION_URLS_H_
 
 #include <string>
 
 #include "base/strings/string16.h"
@@ skipping 20 matching lines @@
 
 // Canonical URLs for the Chrome Webstore. You probably want to use one of
 // the calls below rather than using one of these constants directly, since
 // the active extensions embedder may provide its own webstore URLs.
 extern const char kChromeWebstoreBaseURL[];
 extern const char kChromeWebstoreUpdateURL[];
 
 // Returns the URL prefix for the extension/apps gallery. Can be set via the
 // --apps-gallery-url switch. The URL returned will not contain a trailing
 // slash. Do not use this as a prefix/extent for the store.
-std::string GetWebstoreLaunchURL();
+GURL GetWebstoreLaunchURL();
 
 // Returns the URL to the extensions category on the Web Store. This is
 // derived from GetWebstoreLaunchURL().
 std::string GetWebstoreExtensionsCategoryURL();
 
 // Returns the URL prefix for an item in the extension/app gallery. This URL
 // will contain a trailing slash and should be concatenated with an item ID
 // to get the item detail URL.
 std::string GetWebstoreItemDetailURLPrefix();
 
@@ skipping 26 matching lines @@
 // Returns whether the URL is the webstore update URL (just considering host
 // and path, not scheme, query, etc.)
 bool IsWebstoreUpdateUrl(const GURL& update_url);
 
 // Returns true if the URL points to an extension blacklist.
 bool IsBlacklistUpdateUrl(const GURL& url);
 
 }  // namespace extension_urls
 
 #endif  // EXTENSIONS_COMMON_EXTENSION_URLS_H_