Create MediaRouterActionController and MediaRouterUIService

chrome/browser/extensions/component_migration_helper.cc

 // Copyright 2016 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/component_migration_helper.h"
 
 #include "base/stl_util.h"
 #include "base/values.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system_impl.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/ui/toolbar/component_toolbar_actions_factory.h"
 #include "chrome/common/pref_names.h"
 #include "components/prefs/pref_registry_simple.h"
 #include "components/prefs/pref_service.h"
 #include "components/prefs/scoped_user_pref_update.h"
 #include "content/public/browser/browser_context.h"
 #include "extensions/browser/extension_registry.h"
 #include "extensions/common/feature_switch.h"
 
 namespace extensions {
 
@@ skipping 63 matching lines @@
     bool success =
         migration_pref->GetBoolean(component_action_id, &component_action_pref);
     DCHECK(success);  // Shouldn't fail, but can in case of pref corruption.
   }
 
   if (!has_component_action_pref && extension_was_installed) {
     SetComponentActionPref(component_action_id, true);
     component_action_pref = true;
   }
 
-  if (component_action_pref &&
-      !delegate_->HasComponentAction(component_action_id)) {
-    delegate_->AddComponentAction(component_action_id);
+  if (component_action_pref) {

[mark a. foltz, 2016/09/09 17:48:28]

Just so I understand - this code is here to ensure that users with the extension
or a pre-existing |component_action_pref| force
prefs::kMediaRouterAlwaysShowActionIcon to true.

I think this makes sense; we want the "checked" status of the context menu item
to reflect that the action will remain in the toolbar.

However, since it's a syncable pref, this will effectively enable the action
across all of the user's profiles (even if they only had the extension on one of
them).

I think that's okay as well; I consider this to be an extension of the toolbar
model, which is also synced. 

+    if (component_action_id ==
+        ComponentToolbarActionsFactory::kMediaRouterActionId) {
+      pref_service_->SetBoolean(prefs::kMediaRouterAlwaysShowActionIcon,

[mark a. foltz, 2016/09/09 17:48:28]

Can this only be set if the current value is not already true?  I believe this
will write prefs to disk.

Suggest factoring out a function to check-and-set the pref.

+                                true);
+    }
+    if (!delegate_->HasComponentAction(component_action_id))
+      delegate_->AddComponentAction(component_action_id);
   }
 }
 
 void ComponentMigrationHelper::OnFeatureDisabled(
     const std::string& component_action_id) {
   std::vector<ExtensionId> extension_ids =
       GetExtensionIdsForActionId(component_action_id);
   DCHECK(!extension_ids.empty());
 
   enabled_actions_.erase(component_action_id);
   RemoveComponentActionPref(component_action_id);
 
+  if (component_action_id ==

[mark a. foltz, 2016/09/09 17:48:28]

If the feature is disabled, we should not be creating the action at all, IIUC. I
would be okay with leaving the existing pref value for the next time the MR is
re-enabled.

+      ComponentToolbarActionsFactory::kMediaRouterActionId) {
+    pref_service_->SetBoolean(prefs::kMediaRouterAlwaysShowActionIcon,
+                              false);
+  }
+
   if (FeatureSwitch::extension_action_redesign()->IsEnabled() &&
       delegate_->HasComponentAction(component_action_id))
     delegate_->RemoveComponentAction(component_action_id);
 }
 
 void ComponentMigrationHelper::OnActionRemoved(
     const std::string& component_action_id) {
   // Record preference for the future.
   SetComponentActionPref(component_action_id, false);
 
   // Remove the action.
   if (delegate_->HasComponentAction(component_action_id))
     delegate_->RemoveComponentAction(component_action_id);
 }
 
 void ComponentMigrationHelper::OnExtensionReady(
     content::BrowserContext* browser_context,
     const Extension* extension) {
   const ExtensionId& extension_id = extension->id();
   const std::string& component_action_id =
       GetActionIdForExtensionId(extension_id);
   if (component_action_id.empty())
     return;
   if (base::ContainsKey(enabled_actions_, component_action_id)) {
     UnloadExtension(extension_id);
     SetComponentActionPref(component_action_id, true);
 
+    // We treat installation of the cast extension as a signal to permanently
+    // show the icon in the toolbar.
+    if (component_action_id ==

[mark a. foltz, 2016/09/09 17:48:28]

Please check-and-set the pref.

+        ComponentToolbarActionsFactory::kMediaRouterActionId) {
+      pref_service_->SetBoolean(prefs::kMediaRouterAlwaysShowActionIcon,
+                                true);
+    }
+
     if (!delegate_->HasComponentAction(component_action_id))
       delegate_->AddComponentAction(component_action_id);
   }
 }
 
 void ComponentMigrationHelper::SetComponentActionPref(
     const std::string& component_action_id,
     bool enabled) {
   DictionaryPrefUpdate update(pref_service_,
                               ::prefs::kToolbarMigratedComponentActionStatus);
@@ skipping 32 matching lines @@
 std::string ComponentMigrationHelper::GetActionIdForExtensionId(
     const ExtensionId& extension_id) const {
   for (const auto& i : migrated_actions_) {
     if (i.second == extension_id)
       return i.first;
   }
   return "";
 }
 
 }  // namespace extensions