Create MediaRouterActionController and MediaRouterUIService

chrome/browser/extensions/component_migration_helper.h

Index: chrome/browser/extensions/component_migration_helper.h
diff --git a/chrome/browser/extensions/component_migration_helper.h b/chrome/browser/extensions/component_migration_helper.h
index 66f938ed4a1a7f2603d056981158b9995abea3a8..257d2ea8be5b82b73db340f94fed1f0bd1c7f2e3 100644
--- a/chrome/browser/extensions/component_migration_helper.h
+++ b/chrome/browser/extensions/component_migration_helper.h
@@ -107,11 +107,14 @@ class ComponentMigrationHelper : public ExtensionRegistryObserver {
   void OnExtensionReady(content::BrowserContext* browser_context,
                         const Extension* extension) override;
 
- protected:
-  // Protected for unit testing.
+  // Gets and sets the preference for whether to put the component action with
+  // the given ID on the toolbar (or in the overflow menu).
+  // GetComponentActionPref() requires that the pref has already been set.
+  bool GetComponentActionPref(const std::string& component_action_id) const;
   void SetComponentActionPref(const std::string& component_action_id,

[Devlin, 2016/09/15 21:08:41]

nit: this is only used by tests, right?  Do we need to make it public (or can we
make it public through a ForTesting() wrapper)?

[takumif, 2016/09/16 21:04:05]

This will be used by MRAction (http://crrev.com/2332693003) for toggling the
"always show" option.

                               bool enabled);
 
+ protected:
   // A set of component action ids whose features are currently enabled.
   // Protected for unit testing.
   std::set<std::string> enabled_actions_;