DOMStorageContextImpl that's implemented in terms of the new dom_storage classes.

content/browser/browser_context.cc

 // Copyright (c) 2012 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 "content/public/browser/browser_context.h"
 
 #include "content/browser/appcache/chrome_appcache_service.h"
 #include "content/browser/fileapi/browser_file_system_helper.h"
 #include "content/browser/in_process_webkit/dom_storage_context_impl.h"
 #include "content/browser/in_process_webkit/indexed_db_context_impl.h"
@@ skipping 16 matching lines @@
 // Key names on BrowserContext.
 static const char* kAppCacheServicKeyName = "content_appcache_service_tracker";
 static const char* kDatabaseTrackerKeyName = "content_database_tracker";
 static const char* kDOMStorageContextKeyName = "content_dom_storage_context";
 static const char* kFileSystemContextKeyName = "content_file_system_context";
 static const char* kIndexedDBContextKeyName = "content_indexed_db_context";
 static const char* kQuotaManagerKeyName = "content_quota_manager";
 
 namespace content {
 
+namespace {
+
 void CreateQuotaManagerAndClients(BrowserContext* context) {
   if (context->GetUserData(kQuotaManagerKeyName)) {
     DCHECK(context->GetUserData(kDatabaseTrackerKeyName));
     DCHECK(context->GetUserData(kDOMStorageContextKeyName));
     DCHECK(context->GetUserData(kFileSystemContextKeyName));
     DCHECK(context->GetUserData(kIndexedDBContextKeyName));
     return;
   }
 
   // All of the clients have to be created and registered with the
@@ skipping 61 matching lines @@
 }
 
 void SaveSessionStateOnIOThread(ResourceContext* resource_context) {
   resource_context->GetRequestContext()->cookie_store()->GetCookieMonster()->
       SaveSessionCookies();
   ResourceContext::GetAppCacheService(resource_context)->set_save_session_state(
       true);
 }
 
 void SaveSessionStateOnWebkitThread(
-    scoped_refptr<DOMStorageContextImpl> dom_storage_context,
     scoped_refptr<IndexedDBContextImpl> indexed_db_context) {
-  dom_storage_context->SaveSessionState();
   indexed_db_context->SaveSessionState();
 }
 
 void PurgeMemoryOnIOThread(ResourceContext* resource_context) {
   ResourceContext::GetAppCacheService(resource_context)->PurgeMemory();
 }
 
-void PurgeMemoryOnWebkitThread(
-    scoped_refptr<DOMStorageContextImpl> dom_storage_context) {
-  dom_storage_context->PurgeMemory();
+DOMStorageContextImpl* GetDOMStorageContextImpl(BrowserContext* context) {
+  return static_cast<DOMStorageContextImpl*>(
+      BrowserContext::GetDOMStorageContext(context));
 }
 
+}  // namespace
+
 QuotaManager* BrowserContext::GetQuotaManager(BrowserContext* context) {
   CreateQuotaManagerAndClients(context);
   return UserDataAdapter<QuotaManager>::Get(context, kQuotaManagerKeyName);
 }
 
 DOMStorageContext* BrowserContext::GetDOMStorageContext(
     BrowserContext* context) {
   CreateQuotaManagerAndClients(context);
   return UserDataAdapter<DOMStorageContextImpl>::Get(
       context, kDOMStorageContextKeyName);
@@ skipping 38 matching lines @@
 void BrowserContext::SaveSessionState(BrowserContext* browser_context) {
   GetDatabaseTracker(browser_context)->SaveSessionState();
 
   if (BrowserThread::IsMessageLoopValid(BrowserThread::IO)) {
     BrowserThread::PostTask(
         BrowserThread::IO, FROM_HERE,
         base::Bind(&SaveSessionStateOnIOThread,
                    browser_context->GetResourceContext()));
   }
 
+  GetDOMStorageContextImpl(browser_context)->SaveSessionState();

[michaeln, 2012/03/17 03:52:22]

the gist of these changes is to remove the WEBKIT_DEPRECATED thread dependency,
now we just call the method and the impl class deal with threading issues

+
   if (BrowserThread::IsMessageLoopValid(BrowserThread::WEBKIT_DEPRECATED)) {
-    DOMStorageContextImpl* dom_context = static_cast<DOMStorageContextImpl*>(
-        GetDOMStorageContext(browser_context));
     IndexedDBContextImpl* indexed_db = static_cast<IndexedDBContextImpl*>(
         GetIndexedDBContext(browser_context));
     BrowserThread::PostTask(
         BrowserThread::WEBKIT_DEPRECATED, FROM_HERE,
         base::Bind(&SaveSessionStateOnWebkitThread,
-                   make_scoped_refptr(dom_context),
                    make_scoped_refptr(indexed_db)));
   }
 }
 
 void BrowserContext::ClearLocalOnDestruction(BrowserContext* browser_context) {
-  DOMStorageContextImpl* dom_context = static_cast<DOMStorageContextImpl*>(
-      GetDOMStorageContext(browser_context));
-  dom_context->set_clear_local_state_on_exit(true);
+  GetDOMStorageContextImpl(browser_context)->SetClearLocalState(true);
 
   IndexedDBContextImpl* indexed_db = static_cast<IndexedDBContextImpl*>(
       GetIndexedDBContext(browser_context));
   indexed_db->set_clear_local_state_on_exit(true);
 
   GetDatabaseTracker(browser_context)->SetClearLocalStateOnExit(true);
 
   if (BrowserThread::IsMessageLoopValid(BrowserThread::IO)) {
     BrowserThread::PostTask(
           BrowserThread::IO, FROM_HERE,
           base::Bind(&appcache::AppCacheService::set_clear_local_state_on_exit,
               base::Unretained(GetAppCacheService(browser_context)), true));
   }
 }
 
 void BrowserContext::PurgeMemory(BrowserContext* browser_context) {
   if (BrowserThread::IsMessageLoopValid(BrowserThread::IO)) {
     BrowserThread::PostTask(
         BrowserThread::IO, FROM_HERE,
         base::Bind(&PurgeMemoryOnIOThread,
                    browser_context->GetResourceContext()));
   }
 
-  if (BrowserThread::IsMessageLoopValid(BrowserThread::WEBKIT_DEPRECATED)) {
-    DOMStorageContextImpl* dom_context = static_cast<DOMStorageContextImpl*>(
-        GetDOMStorageContext(browser_context));
-    BrowserThread::PostTask(
-        BrowserThread::WEBKIT_DEPRECATED, FROM_HERE,
-        base::Bind(&PurgeMemoryOnWebkitThread,
-                   make_scoped_refptr(dom_context)));
-  }
+  GetDOMStorageContextImpl(browser_context)->PurgeMemory();
 }
 
 BrowserContext::~BrowserContext() {
   // These message loop checks are just to avoid leaks in unittests.
   if (GetUserData(kDatabaseTrackerKeyName) &&
       BrowserThread::IsMessageLoopValid(BrowserThread::FILE)) {
     BrowserThread::PostTask(
         BrowserThread::FILE, FROM_HERE,
         base::Bind(&webkit_database::DatabaseTracker::Shutdown,
                    GetDatabaseTracker(this)));
   }
 
+#ifdef ENABLE_NEW_DOM_STORAGE_BACKEND
+  if (GetUserData(kDOMStorageContextKeyName))
+    GetDOMStorageContextImpl(this)->Shutdown();

[michaeln, 2012/03/17 03:52:22]

adding an explicit shutdown method since relying on destruction of recounted
objects is squishy

(historical note: prior to content api machinations, DOMStorageContext[Impl]
employed delete semantics, but when delete semantics were change to refcounting
semantics nothing was done to tighten up the shutdown logic)

+#else
   if (GetUserData(kDOMStorageContextKeyName) &&
       BrowserThread::IsMessageLoopValid(BrowserThread::WEBKIT_DEPRECATED)) {
     DOMStorageContextImpl* dom_storage_context =
         (static_cast<UserDataAdapter<DOMStorageContextImpl>*>(
             GetUserData(kDOMStorageContextKeyName)))->release();
     BrowserThread::ReleaseSoon(
         BrowserThread::WEBKIT_DEPRECATED, FROM_HERE, dom_storage_context);
   }
+#endif
 }
 
 }  // namespace content