[extensions] Stop parsing webstore urls so much

chrome/common/extensions/chrome_extensions_client.cc

 // 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.
 
 #include "chrome/common/extensions/chrome_extensions_client.h"
 
 #include <memory>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 263 matching lines @@
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kAppsGalleryURL))
     gallery_prefix =
         base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
             switches::kAppsGalleryURL);
   if (base::EndsWith(gallery_prefix, "/", base::CompareCase::SENSITIVE))
     gallery_prefix = gallery_prefix.substr(0, gallery_prefix.length() - 1);
   return gallery_prefix;
 }
 
-std::string ChromeExtensionsClient::GetWebstoreUpdateURL() const {
+const GURL& ChromeExtensionsClient::GetWebstoreUpdateURL() const {
+  // Browser tests like to alter the command line at runtime with new update

[Devlin, 2016/11/11 23:11:30]

:(

+  // URLs. Just update the cached value of the update url (to avoid reparsing
+  // it) if the value has changed.
   base::CommandLine* cmdline = base::CommandLine::ForCurrentProcess();
-  if (cmdline->HasSwitch(switches::kAppsGalleryUpdateURL))
-    return cmdline->GetSwitchValueASCII(switches::kAppsGalleryUpdateURL);
-  else
-    return extension_urls::GetDefaultWebstoreUpdateUrl().spec();
+  if (cmdline->HasSwitch(switches::kAppsGalleryUpdateURL)) {
+    std::string url =
+        cmdline->GetSwitchValueASCII(switches::kAppsGalleryUpdateURL);
+    if (webstore_update_url_ != url)
+      webstore_update_url_ = GURL(url);
+  } else if (webstore_update_url_.is_empty()) {
+    webstore_update_url_ = GURL(extension_urls::GetDefaultWebstoreUpdateUrl());
+  }
+  return webstore_update_url_;
 }
 
 bool ChromeExtensionsClient::IsBlacklistUpdateURL(const GURL& url) const {
   // The extension blacklist URL is returned from the update service and
   // therefore not determined by Chromium. If the location of the blacklist file
   // ever changes, we need to update this function. A DCHECK in the
   // ExtensionUpdater ensures that we notice a change. This is the full URL
   // of a blacklist:
   // http://www.gstatic.com/chrome/extensions/blacklist/l_0_0_0_7.txt
   return base::StartsWith(url.spec(), kExtensionBlocklistUrlPrefix,
@@ skipping 34 matching lines @@
     const {
   return GetCurrentChannel() == version_info::Channel::UNKNOWN;
 }
 
 // static
 ChromeExtensionsClient* ChromeExtensionsClient::GetInstance() {
   return g_client.Pointer();
 }
 
 }  // namespace extensions