Google Now Extension Auto Download

Added support to download a finch guided extension for CrOS builds
with the app list extension build bit enabled.

BUG=457335

Review URL: https://codereview.chromium.org/775193003

Cr-Commit-Position: refs/heads/master@{#316334}

chrome/browser/extensions/external_component_loader.cc

@@ -21,6 +21,10 @@
 #include "chromeos/chromeos_switches.h"
 #endif
 
+#if defined(ENABLE_APP_LIST) && defined(OS_CHROMEOS)
+#include "chrome/browser/ui/app_list/google_now_extension.h"
+#endif
+
 namespace extensions {
 
 ExternalComponentLoader::ExternalComponentLoader(Profile* profile)
@@ -85,6 +89,14 @@ void ExternalComponentLoader::StartLoading() {
   }
 #endif
 
+#if defined(ENABLE_APP_LIST) && defined(OS_CHROMEOS)
+  std::string google_now_extension_id;
+  if (GetGoogleNowExtensionId(&google_now_extension_id)) {
+    prefs_->SetString(google_now_extension_id + ".external_update_url",
+                      extension_urls::GetWebstoreUpdateUrl().spec());
+  }
+#endif
+
   LoadFinished();
 }
 

chrome/browser/ui/app_list/google_now_extension.cc

+// Copyright 2015 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/ui/app_list/google_now_extension.h"
+
+#include "components/variations/variations_associated_data.h"
+
+namespace {
+const char kGoogleNowExtensionFieldTrialName[] = "GoogleNowExtension";
+};  // namespace
+
+bool GetGoogleNowExtensionId(std::string* extension_id) {
+  *extension_id = variations::GetVariationParamValue(
+      kGoogleNowExtensionFieldTrialName, "id");
+  return !extension_id->empty();
+}

chrome/browser/ui/app_list/google_now_extension.h

+// Copyright 2015 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 CHROME_BROWSER_UI_APP_LIST_GOOGLE_NOW_EXTENSION_H_
+#define CHROME_BROWSER_UI_APP_LIST_GOOGLE_NOW_EXTENSION_H_
+
+#include <string>
+
+// Returns true and sets |extension_id| if extension experiment enabled
+//         false if no experiment or |extension_id| is empty.
+bool GetGoogleNowExtensionId(std::string* extension_id);
+
+#endif  // CHROME_BROWSER_UI_APP_LIST_GOOGLE_NOW_EXTENSION_H_

chrome/chrome_browser_ui.gypi

@@ -2364,6 +2364,8 @@
       'browser/ui/app_list/extension_uninstaller.h',
       'browser/ui/app_list/fast_show_pickler.cc',
       'browser/ui/app_list/fast_show_pickler.h',
+      'browser/ui/app_list/google_now_extension.cc',
+      'browser/ui/app_list/google_now_extension.h',
       'browser/ui/app_list/launcher_page_event_dispatcher.cc',
       'browser/ui/app_list/launcher_page_event_dispatcher.h',
       'browser/ui/app_list/model_pref_updater.cc',