4 files changed, 60 insertions, 2 deletions
diff --git a/content/child/fileapi/webfilesystem_impl.cc b/content/child/fileapi/webfilesystem_impl.cc
index 052bce4..29a7780 100644
--- a/content/child/fileapi/webfilesystem_impl.cc
+++ b/content/child/fileapi/webfilesystem_impl.cc
@@ -43,6 +43,9 @@ class CallbacksMap;
 base::LazyInstance<base::ThreadLocalPointer<CallbacksMap> >::Leaky
     g_callbacks_map_tls = LAZY_INSTANCE_INITIALIZER;
 
+base::LazyInstance<base::ThreadLocalPointer<WebFileSystemImpl> >::Leaky
+    g_webfilesystem_tls = LAZY_INSTANCE_INITIALIZER;
+
 // TODO(kinuko): Integrate this into WebFileSystemImpl when blink side
 // becomes ready to make WebFileSystemImpl thread-local.
 class CallbacksMap : public WorkerTaskRunner::Observer {
@@ -312,11 +315,33 @@ void CreateSnapshotFileCallbackAdapter(
 
 }  // namespace
 
-WebFileSystemImpl::~WebFileSystemImpl() {
+WebFileSystemImpl* WebFileSystemImpl::ThreadSpecificInstance(
+    base::MessageLoopProxy* main_thread_loop) {
+  if (g_webfilesystem_tls.Pointer()->Get())
+    return g_webfilesystem_tls.Pointer()->Get();
+  WebFileSystemImpl* filesystem = new WebFileSystemImpl(main_thread_loop);
+  if (WorkerTaskRunner::Instance()->CurrentWorkerId())
+    WorkerTaskRunner::Instance()->AddStopObserver(filesystem);
+  return filesystem;
+}
+
+void WebFileSystemImpl::DeleteThreadSpecificInstance() {
+  DCHECK(!WorkerTaskRunner::Instance()->CurrentWorkerId());
+  if (g_webfilesystem_tls.Pointer()->Get())
+    delete g_webfilesystem_tls.Pointer()->Get();
 }
 
 WebFileSystemImpl::WebFileSystemImpl(base::MessageLoopProxy* main_thread_loop)
     : main_thread_loop_(main_thread_loop) {
+  g_webfilesystem_tls.Pointer()->Set(this);
+}
+
+WebFileSystemImpl::~WebFileSystemImpl() {
+  g_webfilesystem_tls.Pointer()->Set(NULL);
+}
+
+void WebFileSystemImpl::OnWorkerRunLoopStopped() {
+  delete this;
 }
 
 void WebFileSystemImpl::move(
diff --git a/content/child/fileapi/webfilesystem_impl.h b/content/child/fileapi/webfilesystem_impl.h
index d9a2584..3e88982 100644
--- a/content/child/fileapi/webfilesystem_impl.h
+++ b/content/child/fileapi/webfilesystem_impl.h
@@ -9,6 +9,7 @@
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "third_party/WebKit/public/platform/WebFileSystem.h"
+#include "webkit/child/worker_task_runner.h"
 
 namespace base {
 class MessageLoopProxy;
@@ -22,11 +23,25 @@ class WebFileWriterClient;
 
 namespace content {
 
-class WebFileSystemImpl : public WebKit::WebFileSystem {
+class WebFileSystemImpl
+    : public WebKit::WebFileSystem,
+      public webkit_glue::WorkerTaskRunner::Observer {
  public:
+  // Returns thread-specific instance.
+  static WebFileSystemImpl* ThreadSpecificInstance(
+      base::MessageLoopProxy* main_thread_loop);
+
+  // Deletes thread-specific instance (if exists). For workers it deletes
+  // itself in OnWorkerRunLoopStopped(), but for an instance created on the
+  // main thread this method must be called.
+  static void DeleteThreadSpecificInstance();
+
   explicit WebFileSystemImpl(base::MessageLoopProxy* main_thread_loop);
   virtual ~WebFileSystemImpl();
 
+  // webkit_glue::WorkerTaskRunner::Observer implementation.
+  virtual void OnWorkerRunLoopStopped() OVERRIDE;
+
   // WebFileSystem implementation.
   virtual void move(
       const WebKit::WebURL& src_path,
diff --git a/content/renderer/renderer_webkitplatformsupport_impl.cc b/content/renderer/renderer_webkitplatformsupport_impl.cc
index d5156a1..c9219ed 100644
--- a/content/renderer/renderer_webkitplatformsupport_impl.cc
+++ b/content/renderer/renderer_webkitplatformsupport_impl.cc
@@ -225,6 +225,10 @@ RendererWebKitPlatformSupportImpl::RendererWebKitPlatformSupportImpl()
 }
 
 RendererWebKitPlatformSupportImpl::~RendererWebKitPlatformSupportImpl() {
+#ifdef USE_THREADLOCAL_WEBFILESYSTEM
+  // TODO(kinuko): Delete this ifdef after blink side switch's over.
+  WebFileSystemImpl::DeleteThreadSpecificInstance();
+#endif
 }
 
 //------------------------------------------------------------------------------
@@ -374,9 +378,14 @@ WebIDBFactory* RendererWebKitPlatformSupportImpl::idbFactory() {
 //------------------------------------------------------------------------------
 
 WebFileSystem* RendererWebKitPlatformSupportImpl::fileSystem() {
+#ifdef USE_THREADLOCAL_WEBFILESYSTEM
+  // TODO(kinuko): Delete this ifdef after blink side switch's over.
+  return WebFileSystemImpl::ThreadSpecificInstance(child_thread_loop_.get());
+#else
   if (!web_file_system_)
     web_file_system_.reset(new WebFileSystemImpl(child_thread_loop_.get()));
   return web_file_system_.get();
+#endif
 }
 
 //------------------------------------------------------------------------------
diff --git a/content/worker/worker_webkitplatformsupport_impl.cc b/content/worker/worker_webkitplatformsupport_impl.cc
index 144db959..a4de2c8 100644
--- a/content/worker/worker_webkitplatformsupport_impl.cc
+++ b/content/worker/worker_webkitplatformsupport_impl.cc
@@ -86,6 +86,10 @@ WorkerWebKitPlatformSupportImpl::WorkerWebKitPlatformSupportImpl(
 }
 
 WorkerWebKitPlatformSupportImpl::~WorkerWebKitPlatformSupportImpl() {
+#ifdef USE_THREADLOCAL_WEBFILESYSTEM
+  // TODO(kinuko): Delete this ifdef after blink side switch's over.
+  WebFileSystemImpl::DeleteThreadSpecificInstance();
+#endif
 }
 
 WebClipboard* WorkerWebKitPlatformSupportImpl::clipboard() {
@@ -98,9 +102,14 @@ WebMimeRegistry* WorkerWebKitPlatformSupportImpl::mimeRegistry() {
 }
 
 WebFileSystem* WorkerWebKitPlatformSupportImpl::fileSystem() {
+#ifdef USE_THREADLOCAL_WEBFILESYSTEM
+  // TODO(kinuko): Delete this ifdef after blink side switch's over.
+  return WebFileSystemImpl::ThreadSpecificInstance(child_thread_loop_.get());
+#else
   if (!web_file_system_)
     web_file_system_.reset(new WebFileSystemImpl(child_thread_loop_.get()));
   return web_file_system_.get();
+#endif
 }
 
 WebFileUtilities* WorkerWebKitPlatformSupportImpl::fileUtilities() {