Reland r50296 which removes some uses of CookieMonster on the UI thread.

chrome/browser/extensions/extension_data_deleter.cc

Index: chrome/browser/extensions/extension_data_deleter.cc
diff --git a/chrome/browser/extensions/extension_data_deleter.cc b/chrome/browser/extensions/extension_data_deleter.cc
index 98cf4330643218cfb59103f96eb5142d758ed874..1a9f84e6ffc3d4e03db9862e41c75f6b3a676f39 100644
--- a/chrome/browser/extensions/extension_data_deleter.cc
+++ b/chrome/browser/extensions/extension_data_deleter.cc
@@ -23,18 +23,28 @@ ExtensionDataDeleter::ExtensionDataDeleter(Profile* profile,
 
 void ExtensionDataDeleter::StartDeleting() {
   DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
+
+  ChromeThread::PostTask(
+      ChromeThread::IO, FROM_HERE,
+      NewRunnableMethod(this, &ExtensionDataDeleter::DeleteCookiesOnIOThread));
+
+  ChromeThread::PostTask(
+      ChromeThread::WEBKIT, FROM_HERE,
+      NewRunnableMethod(
+          this, &ExtensionDataDeleter::DeleteLocalStorageOnWebkitThread));
+
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(
+          this, &ExtensionDataDeleter::DeleteDatabaseOnFileThread));
+}
+
+void ExtensionDataDeleter::DeleteCookiesOnIOThread() {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
   net::CookieMonster* cookie_monster =
       extension_request_context_->GetCookieStore()->GetCookieMonster();
   if (cookie_monster)
     cookie_monster->DeleteAllForURL(extension_url_, true);
-
-  ChromeThread::PostTask(ChromeThread::WEBKIT, FROM_HERE,
-      NewRunnableMethod(this,
-          &ExtensionDataDeleter::DeleteLocalStorageOnWebkitThread));
-
-  ChromeThread::PostTask(ChromeThread::FILE, FROM_HERE,
-      NewRunnableMethod(this,
-          &ExtensionDataDeleter::DeleteDatabaseOnFileThread));
 }
 
 void ExtensionDataDeleter::DeleteDatabaseOnFileThread() {