Made it possible to tell whether an extension is being installed or updated.

chrome/browser/extensions/webstore_startup_installer_browsertest.cc

 // Copyright (c) 2012 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 "base/command_line.h"
 #include "base/stringprintf.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/extensions/extension_host.h"
 #include "chrome/browser/extensions/extension_install_ui.h"
 #include "chrome/browser/extensions/extension_service.h"
@@ skipping 271 matching lines @@
 
   bool saw_install() { return saw_install_; }
 
   int browser_open_count() { return browser_open_count_; }
 
   // NotificationObserver interface.
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE {
     if (type == chrome::NOTIFICATION_EXTENSION_INSTALLED) {
-      const Extension* extension = content::Details<Extension>(details).ptr();
+      const Extension* extension =
+          content::Details<const extensions::InstalledExtensionInfo>(details)->
+              extension;
       ASSERT_TRUE(extension != NULL);
       EXPECT_EQ(extension->id(), kTestExtensionId);
       saw_install_ = true;
     } else if (type == chrome::NOTIFICATION_BROWSER_OPENED) {
       browser_open_count_++;
     } else {
       ASSERT_TRUE(false) << "Unexpected notification type : " << type;
     }
   }
 
@@ skipping 51 matching lines @@
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   command_line->AppendSwitchASCII(
       switches::kLimitedInstallFromWebstore, "2");
   helper.LimitedInstallFromWebstore(*command_line, browser()->profile(),
       MessageLoop::QuitWhenIdleClosure());
   MessageLoop::current()->Run();
 
   EXPECT_TRUE(saw_install());
   EXPECT_EQ(0, browser_open_count());
 }