When in the task runner MessageLoop::current() returns NULL. Use the task...

When in the task runner MessageLoop::current() returns NULL. Use the task runner instead of MessageLoop::current() to PostTask.

BUG=392621

Review URL: https://codereview.chromium.org/472843002

Cr-Commit-Position: refs/heads/master@{#289670}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@289670 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/service_worker/service_worker_cache_storage.cc

@@ -208,7 +208,7 @@ class ServiceWorkerCacheStorage::SimpleCacheLoader
       base::DeleteFile(path, /* recursive */ true);
 
     // Jump straight into LoadCache on the same thread.
-    base::MessageLoopProxy::current()->PostTask(
+    cache_task_runner_->PostTask(
         FROM_HERE,
         base::Bind(&SimpleCacheLoader::LoadCreateDirectoryInPool,
                    this,