Initialize ServiceWorkerContextCore with a message loop for the disk cache to use.

content/browser/service_worker/service_worker_context_core.cc

Index: content/browser/service_worker/service_worker_context_core.cc
diff --git a/content/browser/service_worker/service_worker_context_core.cc b/content/browser/service_worker/service_worker_context_core.cc
index 7a8e3860eb70646f783ac7050d15d39f5842d4cd..3e6e0538e75f68a0463aece2898603cee7a68451 100644
--- a/content/browser/service_worker/service_worker_context_core.cc
+++ b/content/browser/service_worker/service_worker_context_core.cc
@@ -5,6 +5,7 @@
 #include "content/browser/service_worker/service_worker_context_core.h"
 
 #include "base/files/file_path.h"
+#include "base/message_loop/message_loop_proxy.h"
 #include "base/strings/string_util.h"
 #include "content/browser/service_worker/embedded_worker_registry.h"
 #include "content/browser/service_worker/service_worker_context_observer.h"
@@ -78,11 +79,14 @@ void ServiceWorkerContextCore::ProviderHostIterator::Initialize() {
 ServiceWorkerContextCore::ServiceWorkerContextCore(
     const base::FilePath& path,
     base::SequencedTaskRunner* database_task_runner,
+    base::MessageLoopProxy* disk_cache_thread,
     quota::QuotaManagerProxy* quota_manager_proxy,
     ObserverListThreadSafe<ServiceWorkerContextObserver>* observer_list,
     scoped_ptr<ServiceWorkerProcessManager> process_manager)
-    : storage_(new ServiceWorkerStorage(
-          path, AsWeakPtr(), database_task_runner, quota_manager_proxy)),
+    : weak_factory_(this),
+      storage_(new ServiceWorkerStorage(
+          path, AsWeakPtr(), database_task_runner, disk_cache_thread,
+          quota_manager_proxy)),
       embedded_worker_registry_(new EmbeddedWorkerRegistry(AsWeakPtr())),
       job_coordinator_(new ServiceWorkerJobCoordinator(AsWeakPtr())),
       process_manager_(process_manager.Pass()),
@@ -96,10 +100,7 @@ ServiceWorkerContextCore::~ServiceWorkerContextCore() {
        ++it) {
     it->second->RemoveListener(this);
   }
-  providers_.Clear();
-  storage_.reset();
-  job_coordinator_.reset();
-  embedded_worker_registry_ = NULL;
+  weak_factory_.InvalidateWeakPtrs();
 }
 
 ServiceWorkerProviderHost* ServiceWorkerContextCore::GetProviderHost(