Implement sidebar support for extension action popups

chrome/browser/extensions/extension_system_impl.h

Index: chrome/browser/extensions/extension_system_impl.h
diff --git a/chrome/browser/extensions/extension_system_impl.h b/chrome/browser/extensions/extension_system_impl.h
index 92e24577b9f2ee5c77c92980883cb11fcc94c011..755d56a152191558a9d314467ef0f039b9a49ea8 100644
--- a/chrome/browser/extensions/extension_system_impl.h
+++ b/chrome/browser/extensions/extension_system_impl.h
@@ -56,6 +56,8 @@ class ExtensionSystemImpl : public ExtensionSystem {
   scoped_ptr<ExtensionSet> GetDependentExtensions(
       const Extension* extension) override;
 
+  SidebarManager* sidebar_manager() override;  // shared
+
  private:
   friend class ExtensionSystemSharedFactory;
 
@@ -85,6 +87,7 @@ class ExtensionSystemImpl : public ExtensionSystem {
     QuotaService* quota_service();
     const OneShotEvent& ready() const { return ready_; }
     ContentVerifier* content_verifier();
+    SidebarManager* sidebar_manager();
 
    private:
     Profile* profile_;
@@ -110,6 +113,8 @@ class ExtensionSystemImpl : public ExtensionSystem {
     // For verifying the contents of extensions read from disk.
     scoped_refptr<ContentVerifier> content_verifier_;
 
+    scoped_ptr<SidebarManager> sidebar_manager_;
+
 #if defined(OS_CHROMEOS)
     scoped_ptr<chromeos::DeviceLocalAccountManagementPolicyProvider>
         device_local_account_management_policy_provider_;