Another stab at the Chromium side of storage events. The WebKit side can be found here: https://bugs.webkit.org/show_bug.cgi?id=29655

TEST=Manually inspected that storage events fired.  Will turn on more layout tests in a subsequent patch.
BUG=19972

Review URL: http://codereview.chromium.org/223013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@27756 0039d316-1c4b-4281-b951-d872f2087c98

10 files changed, 189 insertions, 34 deletions

diff --git a/chrome/browser/in_process_webkit/browser_webkitclient_impl.cc b/chrome/browser/in_process_webkit/browser_webkitclient_impl.cc
index 33fc0de..53ced24 100644
--- a/chrome/browser/in_process_webkit/browser_webkitclient_impl.cc
+++ b/chrome/browser/in_process_webkit/browser_webkitclient_impl.cc
@@ -5,6 +5,7 @@
 #include "chrome/browser/in_process_webkit/browser_webkitclient_impl.h"
 
 #include "base/logging.h"
+#include "chrome/browser/in_process_webkit/dom_storage_dispatcher_host.h"
 #include "webkit/api/public/WebData.h"
 #include "webkit/api/public/WebString.h"
 #include "webkit/api/public/WebURL.h"
@@ -105,3 +106,15 @@ BrowserWebKitClientImpl::createSessionStorageNamespace() {
   NOTREACHED();
   return 0;
 }
+
+void BrowserWebKitClientImpl::dispatchStorageEvent(
+    const WebKit::WebString& key, const WebKit::WebString& old_value,
+    const WebKit::WebString& new_value, const WebKit::WebString& origin,
+    bool is_local_storage) {
+  // TODO(jorlow): Implement
+  if (!is_local_storage)
+    return;
+
+  DOMStorageDispatcherHost::DispatchStorageEvent(key, old_value, new_value,
+                                                 origin, is_local_storage);
+}
diff --git a/chrome/browser/in_process_webkit/browser_webkitclient_impl.h b/chrome/browser/in_process_webkit/browser_webkitclient_impl.h
index 546100d..07824db 100644
--- a/chrome/browser/in_process_webkit/browser_webkitclient_impl.h
+++ b/chrome/browser/in_process_webkit/browser_webkitclient_impl.h
@@ -32,6 +32,9 @@ class BrowserWebKitClientImpl : public webkit_glue::WebKitClientImpl {
   virtual WebKit::WebStorageNamespace* createLocalStorageNamespace(
       const WebKit::WebString& path);
   virtual WebKit::WebStorageNamespace* createSessionStorageNamespace();
+  virtual void dispatchStorageEvent(const WebKit::WebString& key,
+      const WebKit::WebString& oldValue, const WebKit::WebString& newValue,
+      const WebKit::WebString& origin, bool isLocalStorage);
 };
 
 #endif  // CHROME_BROWSER_IN_PROCESS_WEBKIT_WEBKIT_CLIENT_IMPL_H_
diff --git a/chrome/browser/in_process_webkit/dom_storage_context.cc b/chrome/browser/in_process_webkit/dom_storage_context.cc
index b22d976..9f763e2 100644
--- a/chrome/browser/in_process_webkit/dom_storage_context.cc
+++ b/chrome/browser/in_process_webkit/dom_storage_context.cc
@@ -14,11 +14,18 @@ DOMStorageContext::DOMStorageContext(WebKitContext* webkit_context)
     : last_storage_area_id_(kFirstStorageAreaId),
       last_storage_namespace_id_(kFirstStorageNamespaceId),
       webkit_context_(webkit_context) {
-  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
 }
 
 DOMStorageContext::~DOMStorageContext() {
+  // This should not go away until all DOM Storage Dispatcher hosts have gone
+  // away.  And they remove themselves from this list.
+  DCHECK(dispatcher_host_set_.empty());
+
+  // If we don't have any work to do on the WebKit thread, bail.
+  if (storage_namespace_map_.empty())
+    return;
   DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
+
   // The storage namespace destructor unregisters the storage namespace, so
   // our iterator becomes invalid.  Thus we just keep deleting the first item
   // until there are none left.
@@ -27,6 +34,7 @@ DOMStorageContext::~DOMStorageContext() {
 }
 
 StorageNamespace* DOMStorageContext::LocalStorage() {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
   StorageNamespace* storage_namespace = GetStorageNamespace(
       kLocalStorageNamespaceId);
   if (storage_namespace)
@@ -40,22 +48,26 @@ StorageNamespace* DOMStorageContext::LocalStorage() {
 }
 
 StorageNamespace* DOMStorageContext::NewSessionStorage() {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
   return StorageNamespace::CreateSessionStorageNamespace(this);
 }
 
 void DOMStorageContext::RegisterStorageArea(StorageArea* storage_area) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
   int64 id = storage_area->id();
   DCHECK(!GetStorageArea(id));
   storage_area_map_[id] = storage_area;
 }
 
 void DOMStorageContext::UnregisterStorageArea(StorageArea* storage_area) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
   int64 id = storage_area->id();
   DCHECK(GetStorageArea(id));
   storage_area_map_.erase(id);
 }
 
 StorageArea* DOMStorageContext::GetStorageArea(int64 id) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
   StorageAreaMap::iterator iter = storage_area_map_.find(id);
   if (iter == storage_area_map_.end())
     return NULL;
@@ -64,6 +76,7 @@ StorageArea* DOMStorageContext::GetStorageArea(int64 id) {
 
 void DOMStorageContext::RegisterStorageNamespace(
     StorageNamespace* storage_namespace) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
   int64 id = storage_namespace->id();
   DCHECK(!GetStorageNamespace(id));
   storage_namespace_map_[id] = storage_namespace;
@@ -71,14 +84,38 @@ void DOMStorageContext::RegisterStorageNamespace(
 
 void DOMStorageContext::UnregisterStorageNamespace(
     StorageNamespace* storage_namespace) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
   int64 id = storage_namespace->id();
   DCHECK(GetStorageNamespace(id));
   storage_namespace_map_.erase(id);
 }
 
 StorageNamespace* DOMStorageContext::GetStorageNamespace(int64 id) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
   StorageNamespaceMap::iterator iter = storage_namespace_map_.find(id);
   if (iter == storage_namespace_map_.end())
     return NULL;
   return iter->second;
 }
+
+void DOMStorageContext::RegisterDispatcherHost(
+    DOMStorageDispatcherHost* dispatcher_host) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
+  DCHECK(dispatcher_host_set_.find(dispatcher_host) ==
+         dispatcher_host_set_.end());
+  dispatcher_host_set_.insert(dispatcher_host);
+}
+
+void DOMStorageContext::UnregisterDispatcherHost(
+    DOMStorageDispatcherHost* dispatcher_host) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
+  DCHECK(dispatcher_host_set_.find(dispatcher_host) !=
+         dispatcher_host_set_.end());
+  dispatcher_host_set_.erase(dispatcher_host);
+}
+
+const DOMStorageContext::DispatcherHostSet*
+DOMStorageContext::GetDispatcherHostSet() const {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
+  return &dispatcher_host_set_;
+}
diff --git a/chrome/browser/in_process_webkit/dom_storage_context.h b/chrome/browser/in_process_webkit/dom_storage_context.h
index ba26ac2..5e85876 100644
--- a/chrome/browser/in_process_webkit/dom_storage_context.h
+++ b/chrome/browser/in_process_webkit/dom_storage_context.h
@@ -7,6 +7,7 @@
 
 #include "base/file_path.h"
 #include "base/hash_tables.h"
+#include "chrome/browser/in_process_webkit/dom_storage_dispatcher_host.h"
 
 class StorageArea;
 class StorageNamespace;
@@ -15,7 +16,8 @@ class WebKitContext;
 // This is owned by WebKitContext and is all the dom storage information that's
 // shared by all the ResourceMessageFilter/DOMStorageDispatcherHosts that share
 // the same profile.  The specifics of responsibilities are fairly well
-// documented here and in StorageNamespace and StorageArea.
+// documented here and in StorageNamespace and StorageArea.  Everything is only
+// to be accessed on the WebKit thread unless noted otherwise.
 class DOMStorageContext {
  public:
   explicit DOMStorageContext(WebKitContext* webkit_context);
@@ -44,6 +46,13 @@ class DOMStorageContext {
   void UnregisterStorageNamespace(StorageNamespace* storage_namespace);
   StorageNamespace* GetStorageNamespace(int64 id);
 
+  // Sometimes an event from one DOM storage dispatcher host requires
+  // communication to all of them.
+  typedef base::hash_set<DOMStorageDispatcherHost*> DispatcherHostSet;
+  void RegisterDispatcherHost(DOMStorageDispatcherHost* dispatcher_host);
+  void UnregisterDispatcherHost(DOMStorageDispatcherHost* dispatcher_host);
+  const DispatcherHostSet* GetDispatcherHostSet() const;
+
   // The special ID used for local storage.
   static const int64 kLocalStorageNamespaceId = 0;
 
@@ -57,6 +66,10 @@ class DOMStorageContext {
   // We're owned by this WebKit context.  Used while instantiating LocalStorage.
   WebKitContext* webkit_context_;
 
+  // All the DOMStorageDispatcherHosts that are attached to us. ONLY USE ON THE
+  // IO THREAD!
+  DispatcherHostSet dispatcher_host_set_;
+
   // Maps ids to StorageAreas.  We do NOT own these objects.  StorageNamespace
   // (which does own them) will notify us when we should remove the entries.
   typedef base::hash_map<int64, StorageArea*> StorageAreaMap;
diff --git a/chrome/browser/in_process_webkit/dom_storage_dispatcher_host.cc b/chrome/browser/in_process_webkit/dom_storage_dispatcher_host.cc
index ac39acb..1856a37 100644
--- a/chrome/browser/in_process_webkit/dom_storage_dispatcher_host.cc
+++ b/chrome/browser/in_process_webkit/dom_storage_dispatcher_host.cc
@@ -13,6 +13,23 @@
 #include "chrome/browser/renderer_host/browser_render_process_host.h"
 #include "chrome/common/render_messages.h"
 
+DOMStorageDispatcherHost* DOMStorageDispatcherHost::current_ = NULL;
+
+DOMStorageDispatcherHost::
+AutoSetCurrentDispatcherHost::AutoSetCurrentDispatcherHost(
+    DOMStorageDispatcherHost* dispatcher_host) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
+  DCHECK(!current_);
+  current_ = dispatcher_host;
+}
+
+DOMStorageDispatcherHost::
+AutoSetCurrentDispatcherHost::~AutoSetCurrentDispatcherHost() {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
+  DCHECK(current_);
+  current_ = NULL;
+}
+
 DOMStorageDispatcherHost::DOMStorageDispatcherHost(
     IPC::Message::Sender* message_sender, WebKitContext* webkit_context,
     WebKitThread* webkit_thread)
@@ -32,6 +49,9 @@ DOMStorageDispatcherHost::~DOMStorageDispatcherHost() {
 }
 
 void DOMStorageDispatcherHost::Init(base::ProcessHandle process_handle) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
+  Context()->RegisterDispatcherHost(this);
+
   DCHECK(!process_handle_);
   process_handle_ = process_handle;
   DCHECK(process_handle_);
@@ -39,6 +59,7 @@ void DOMStorageDispatcherHost::Init(base::ProcessHandle process_handle) {
 
 void DOMStorageDispatcherHost::Shutdown() {
   if (ChromeThread::CurrentlyOn(ChromeThread::IO)) {
+    Context()->UnregisterDispatcherHost(this);
     message_sender_ = NULL;
     if (!ever_used_) {
       // No need to (possibly) spin up the WebKit thread for a no-op.
@@ -58,12 +79,24 @@ void DOMStorageDispatcherHost::Shutdown() {
   DCHECK(!shutdown_);
   shutdown_ = true;
 
-  // TODO(jorlow): If we have any locks or are tracking resources that need to
-  //               be released on the WebKit thread, do it here.
+  // TODO(jorlow): Do stuff that needs to be run on the WebKit thread.  Locks
+  //               and others will likely need this, so let's not delete this
+  //               code even though it doesn't do anyting yet.
 }
 
-bool DOMStorageDispatcherHost::OnMessageReceived(
-    const IPC::Message& message, bool *msg_is_ok) {
+/* static */
+void DOMStorageDispatcherHost::DispatchStorageEvent(const string16& key,
+    const NullableString16& old_value, const NullableString16& new_value,
+    const string16& origin, bool is_local_storage) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
+  DCHECK(current_);
+  current_->webkit_thread_->PostIOThreadTask(FROM_HERE, NewRunnableMethod(
+        current_, &DOMStorageDispatcherHost::OnStorageEvent, key, old_value,
+        new_value, origin, is_local_storage));
+}
+
+bool DOMStorageDispatcherHost::OnMessageReceived(const IPC::Message& message,
+                                                 bool *msg_is_ok) {
   DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
   DCHECK(!shutdown_);
   DCHECK(process_handle_);
@@ -272,6 +305,8 @@ void DOMStorageDispatcherHost::OnSetItem(int64 storage_area_id,
         ViewHostMsg_DOMStorageSetItem::ID, process_handle_);
     return;
   }
+
+  AutoSetCurrentDispatcherHost auto_set(this);
   storage_area->SetItem(key, value, &quota_exception);
   DCHECK(!quota_exception);  // This is tracked by the renderer.
 }
@@ -293,6 +328,8 @@ void DOMStorageDispatcherHost::OnRemoveItem(int64 storage_area_id,
         ViewHostMsg_DOMStorageRemoveItem::ID, process_handle_);
     return;
   }
+
+  AutoSetCurrentDispatcherHost auto_set(this);
   storage_area->RemoveItem(key);
 }
 
@@ -312,5 +349,24 @@ void DOMStorageDispatcherHost::OnClear(int64 storage_area_id) {
         ViewHostMsg_DOMStorageClear::ID, process_handle_);
     return;
   }
+
+  AutoSetCurrentDispatcherHost auto_set(this);
   storage_area->Clear();
 }
+
+void DOMStorageDispatcherHost::OnStorageEvent(const string16& key,
+    const NullableString16& old_value, const NullableString16& new_value,
+    const string16& origin, bool is_local_storage) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
+  DCHECK(is_local_storage);  // Only LocalStorage is implemented right now.
+  DOMStorageType dom_storage_type = is_local_storage ? DOM_STORAGE_LOCAL
+                                                     : DOM_STORAGE_SESSION;
+  const DOMStorageContext::DispatcherHostSet* set =
+      Context()->GetDispatcherHostSet();
+  DOMStorageContext::DispatcherHostSet::const_iterator cur = set->begin();
+  while (cur != set->end()) {
+    (*cur)->Send(new ViewMsg_DOMStorageEvent(key, old_value, new_value, origin,
+                                             dom_storage_type));
+    ++cur;
+  }
+}
diff --git a/chrome/browser/in_process_webkit/dom_storage_dispatcher_host.h b/chrome/browser/in_process_webkit/dom_storage_dispatcher_host.h
index a0d3d77..7b34ad7 100644
--- a/chrome/browser/in_process_webkit/dom_storage_dispatcher_host.h
+++ b/chrome/browser/in_process_webkit/dom_storage_dispatcher_host.h
@@ -29,14 +29,22 @@ class DOMStorageDispatcherHost :
   // Only call from ResourceMessageFilter on the IO thread.
   void Init(base::ProcessHandle process_handle);
 
-  // Only call from ResourceMessageFilter on the IO thread.
+  // Only call from ResourceMessageFilter on the IO thread.  Calls self on the
+  // WebKit thread in some cases.
   void Shutdown();
+
+  // Only call from ResourceMessageFilter on the IO thread.
   bool OnMessageReceived(const IPC::Message& message, bool *msg_is_ok);
 
   // Send a message to the renderer process associated with our
   // message_sender_ via the IO thread.  May be called from any thread.
   void Send(IPC::Message* message);
 
+  // Only call on the WebKit thread.
+  static void DispatchStorageEvent(const string16& key,
+      const NullableString16& old_value, const NullableString16& new_value,
+      const string16& origin, bool is_local_storage);
+
  private:
   friend class base::RefCountedThreadSafe<DOMStorageDispatcherHost>;
   ~DOMStorageDispatcherHost();
@@ -55,12 +63,27 @@ class DOMStorageDispatcherHost :
   void OnRemoveItem(int64 storage_area_id, const string16& key);
   void OnClear(int64 storage_area_id);
 
+  // Only call on the IO thread.
+  void OnStorageEvent(const string16& key, const NullableString16& old_value,
+      const NullableString16& new_value, const string16& origin,
+      bool is_local_storage);
+
   // A shortcut for accessing our context.
   DOMStorageContext* Context() {
     DCHECK(!shutdown_);
-    return webkit_context_->GetDOMStorageContext();
+    return webkit_context_->dom_storage_context();
   }
 
+  // Use whenever there's a chance OnStorageEvent will be called.
+  class AutoSetCurrentDispatcherHost {
+   public:
+    AutoSetCurrentDispatcherHost(DOMStorageDispatcherHost* dispatcher_host);
+    ~AutoSetCurrentDispatcherHost();
+  };
+
+  // Only access on the WebKit thread!  Used for storage events.
+  static DOMStorageDispatcherHost* current_;
+
   // Data shared between renderer processes with the same profile.
   scoped_refptr<WebKitContext> webkit_context_;
 
@@ -87,4 +110,17 @@ class DOMStorageDispatcherHost :
   DISALLOW_IMPLICIT_CONSTRUCTORS(DOMStorageDispatcherHost);
 };
 
+#if defined(COMPILER_GCC)
+namespace __gnu_cxx {
+
+template<>
+struct hash<DOMStorageDispatcherHost*> {
+  std::size_t operator()(DOMStorageDispatcherHost* const& p) const {
+    return reinterpret_cast<std::size_t>(p);
+  }
+};
+
+}  // namespace __gnu_cxx
+#endif
+
 #endif  // CHROME_BROWSER_IN_PROCESS_WEBKIT_DOM_STORAGE_DISPATCHER_HOST_H_
diff --git a/chrome/browser/in_process_webkit/storage_namespace.cc b/chrome/browser/in_process_webkit/storage_namespace.cc
index fa2c74a..fb49259 100644
--- a/chrome/browser/in_process_webkit/storage_namespace.cc
+++ b/chrome/browser/in_process_webkit/storage_namespace.cc
@@ -42,11 +42,11 @@ StorageNamespace* StorageNamespace::CreateSessionStorageNamespace(
 
 StorageNamespace::StorageNamespace(DOMStorageContext* dom_storage_context,
                                    WebStorageNamespace* storage_namespace,
-                                   int64 id, DOMStorageType storage_type)
+                                   int64 id, DOMStorageType dom_storage_type)
     : dom_storage_context_(dom_storage_context),
       storage_namespace_(storage_namespace),
       id_(id),
-      storage_type_(storage_type) {
+      dom_storage_type_(dom_storage_type) {
   DCHECK(dom_storage_context_);
   DCHECK(storage_namespace_);
   dom_storage_context_->RegisterStorageNamespace(this);
@@ -82,12 +82,12 @@ StorageArea* StorageNamespace::GetStorageArea(const string16& origin) {
 }
 
 StorageNamespace* StorageNamespace::Copy() {
-  DCHECK(storage_type_ == DOM_STORAGE_SESSION);
+  DCHECK(dom_storage_type_ == DOM_STORAGE_SESSION);
   int64 id = dom_storage_context_->AllocateStorageNamespaceId();
   DCHECK(!dom_storage_context_->GetStorageNamespace(id));
   WebStorageNamespace* new_storage_namespace = storage_namespace_->copy();
   return new StorageNamespace(dom_storage_context_, new_storage_namespace, id,
-                              storage_type_);
+                              dom_storage_type_);
 }
 
 void StorageNamespace::Close() {
diff --git a/chrome/browser/in_process_webkit/storage_namespace.h b/chrome/browser/in_process_webkit/storage_namespace.h
index 91e0ae6..9752212 100644
--- a/chrome/browser/in_process_webkit/storage_namespace.h
+++ b/chrome/browser/in_process_webkit/storage_namespace.h
@@ -31,7 +31,11 @@ class StorageNamespace {
   StorageNamespace* Copy();
   void Close();
 
+  const DOMStorageContext* dom_storage_context() const {
+    return dom_storage_context_;
+  }
   int64 id() const { return id_; }
+  DOMStorageType dom_storage_type() const { return dom_storage_type_; }
 
  private:
   // Called by the static factory methods above.
@@ -53,7 +57,7 @@ class StorageNamespace {
   int64 id_;
 
   // SessionStorage vs. LocalStorage.
-  const DOMStorageType storage_type_;
+  const DOMStorageType dom_storage_type_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(StorageNamespace);
 };
diff --git a/chrome/browser/in_process_webkit/webkit_context.cc b/chrome/browser/in_process_webkit/webkit_context.cc
index ae647d6..0768284 100644
--- a/chrome/browser/in_process_webkit/webkit_context.cc
+++ b/chrome/browser/in_process_webkit/webkit_context.cc
@@ -9,24 +9,17 @@
 
 WebKitContext::WebKitContext(const FilePath& data_path, bool is_incognito)
     : data_path_(data_path),
-      is_incognito_(is_incognito) {
+      is_incognito_(is_incognito),
+      ALLOW_THIS_IN_INITIALIZER_LIST(
+          dom_storage_context_(new DOMStorageContext(this))) {
 }
 
 WebKitContext::~WebKitContext() {
-  // If a dom storage context was ever created, we need to destroy it on the
-  // WebKit thread.  Luckily we're guaranteed that the WebKit thread is still
-  // alive since the ResourceDispatcherHost (which owns the WebKit thread) goes
-  // away after all the ResourceMessageFilters and the profiles (i.e. all the
-  // objects with a reference to us).
-  if (dom_storage_context_.get()) {
-    MessageLoop* loop = ChromeThread::GetMessageLoop(ChromeThread::WEBKIT);
-    loop->DeleteSoon(FROM_HERE, dom_storage_context_.release());
-  }
-}
-
-DOMStorageContext* WebKitContext::GetDOMStorageContext() {
-  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::WEBKIT));
-  if (!dom_storage_context_.get())
-    dom_storage_context_.reset(new DOMStorageContext(this));
-  return dom_storage_context_.get();
+  // If the WebKit thread was ever spun up, delete the object there.  If we're
+  // on the IO thread, this is safe because the WebKit thread goes away after
+  // the IO.  If we're on the UI thread, we're safe because the UI thread kills
+  // the WebKit thread.
+  MessageLoop* webkit_loop = ChromeThread::GetMessageLoop(ChromeThread::WEBKIT);
+  if (webkit_loop)
+    webkit_loop->DeleteSoon(FROM_HERE, dom_storage_context_.release());
 }
diff --git a/chrome/browser/in_process_webkit/webkit_context.h b/chrome/browser/in_process_webkit/webkit_context.h
index ee4c61b..b359ab0 100644
--- a/chrome/browser/in_process_webkit/webkit_context.h
+++ b/chrome/browser/in_process_webkit/webkit_context.h
@@ -10,6 +10,7 @@
 #include "base/scoped_ptr.h"
 
 class DOMStorageContext;
+class WebKitThread;
 
 // There's one WebKitContext per profile.  Various DispatcherHost classes
 // have a pointer to the Context to store shared state.
@@ -19,9 +20,9 @@ class WebKitContext : public base::RefCountedThreadSafe<WebKitContext> {
 
   const FilePath& data_path() const { return data_path_; }
   bool is_incognito() const { return is_incognito_; }
-
-  // Initialized lazily.  Pointer is valid for the lifetime of this instance.
-  DOMStorageContext* GetDOMStorageContext();
+  DOMStorageContext* dom_storage_context() {
+    return dom_storage_context_.get();
+  }
 
  private:
   friend class base::RefCountedThreadSafe<WebKitContext>;
@@ -31,7 +32,6 @@ class WebKitContext : public base::RefCountedThreadSafe<WebKitContext> {
   const FilePath data_path_;
   const bool is_incognito_;
 
-  // The state for DOM Storage.
   scoped_ptr<DOMStorageContext> dom_storage_context_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(WebKitContext);