Fix crash when you uninstall a permissions-upgrade disabled extension.

chrome/browser/extensions/extension_disabled_infobar_delegate.cc

 // Copyright (c) 2011 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/extension_disabled_infobar_delegate.h"
 
 #include <string>
 
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/extensions/extension_install_ui.h"
@@ skipping 134 matching lines @@
                                       extension_);
   return true;
 }
 
 void ExtensionDisabledInfobarDelegate::Observe(
     NotificationType type,
     const NotificationSource& source,
     const NotificationDetails& details) {
   // TODO(mpcomplete): RemoveInfoBar doesn't seem to always result in us getting
   // deleted.
-  const Extension* extension;
+  const Extension* extension = NULL;
   if (type.value == NotificationType::EXTENSION_LOADED) {
     extension = Details<const Extension>(details).ptr();
   } else {
     DCHECK_EQ(NotificationType::EXTENSION_UNLOADED, type.value);
     UnloadedExtensionInfo* info = Details<UnloadedExtensionInfo>(details).ptr();
-    extension = (info->reason == UnloadedExtensionInfo::DISABLE) ?
-        info->extension : NULL;
+    if (info->reason == UnloadedExtensionInfo::DISABLE ||
+        info->reason == UnloadedExtensionInfo::UNINSTALL)
+      extension = info->extension;
   }
   if (extension == extension_)
     tab_contents_->RemoveInfoBar(this);
 }
 
 
 // Globals --------------------------------------------------------------------
 
 void ShowExtensionDisabledUI(ExtensionService* service, Profile* profile,
                              const Extension* extension) {
   Browser* browser = BrowserList::GetLastActiveWithProfile(profile);
   if (!browser)
     return;
 
   TabContentsWrapper* tab_contents = browser->GetSelectedTabContentsWrapper();
   if (!tab_contents)
     return;
 
   tab_contents->AddInfoBar(new ExtensionDisabledInfobarDelegate(
       tab_contents, service, extension));
 }
 
 void ShowExtensionDisabledDialog(ExtensionService* service, Profile* profile,
                                  const Extension* extension) {
   // This object manages its own lifetime.
   new ExtensionDisabledDialogDelegate(profile, service, extension);
 }