Eliminate all UI thread decoding of extension images....

chrome/browser/cocoa/extensions/extension_action_context_menu.mm

 // Copyright (c) 2010 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.
 
 #import "chrome/browser/cocoa/extensions/extension_action_context_menu.h"
 
 #include "app/l10n_util_mac.h"
 #include "base/sys_string_conversions.h"
 #include "base/task.h"
 #include "chrome/browser/browser_list.h"
@@ skipping 55 matching lines @@
     DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
     // If |extension_| is NULL, then the action was cancelled. Bail.
     if (!extension_)
       return;
 
     Browser* browser = BrowserList::GetLastActive();
     // GetLastActive() returns NULL during testing.
     if (!browser)
       return;
 
-    ExtensionInstallUI client(browser->profile());
-    client.ConfirmUninstall(this, extension_, uninstall_icon->get());
+    install_ui_.reset(new ExtensionInstallUI(browser->profile()));
+    install_ui_->ConfirmUninstall(this, extension_);
   }
 
   // The extension that we're loading the icon for. Weak.
   Extension* extension_;
 
   // The uninstall icon shown by the confirmation dialog.
   scoped_ptr<SkBitmap> uninstall_icon_;
 
+  scoped_ptr<ExtensionInstallUI> install_ui_;
+
   DISALLOW_COPY_AND_ASSIGN(AsyncUninstaller);
 };
 
 @interface ExtensionActionContextMenu(Private)
 // Callback for the context menu items.
 - (void)dispatch:(id)menuItem;
 @end
 
 @implementation ExtensionActionContextMenu
 
@@ skipping 91 matching lines @@
                        NEW_FOREGROUND_TAB, PageTransition::LINK);
       break;
     }
     default:
       NOTREACHED();
       break;
   }
 }
 
 @end