Change so that the extension favicon is read on the UI thread since extension objects should only be accessed on the UI thread.

This also fixes erg's todo to make favicons use RefCountedMemory instead of RefCountedBytes in all places.

BUG=None
TEST=None

Review URL: http://codereview.chromium.org/1028001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@41869 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 7 insertions, 3 deletions

diff --git a/chrome/browser/extensions/extension_dom_ui.cc b/chrome/browser/extensions/extension_dom_ui.cc
index 424dd80e..e9866b1 100644
--- a/chrome/browser/extensions/extension_dom_ui.cc
+++ b/chrome/browser/extensions/extension_dom_ui.cc
@@ -27,8 +27,9 @@ const wchar_t kExtensionURLOverrides[] = L"extensions.chrome_url_overrides";
 
 // Returns a piece of memory with the contents of the file |path|.
 RefCountedMemory* ReadFileData(const FilePath& path) {
-  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
-
+  // TODO(arv): We currently read this on the UI thread since extension objects
+  // can only safely be accessed on the UI thread. Read the file on the FILE
+  // thread and cache the result on the UI thread instead.
   if (path.empty())
     return NULL;
 
@@ -71,7 +72,7 @@ void ExtensionDOMUI::ResetExtensionFunctionDispatcher(
 
 void ExtensionDOMUI::ResetExtensionBookmarkManagerEventRouter() {
   if (CommandLine::ForCurrentProcess()->HasSwitch(
-      switches::kEnableTabbedBookmarkManager)) {
+          switches::kEnableTabbedBookmarkManager)) {
     extension_bookmark_manager_event_router_.reset(
         new ExtensionBookmarkManagerEventRouter(GetProfile(), tab_contents()));
   }
@@ -317,6 +318,9 @@ void ExtensionDOMUI::UnregisterChromeURLOverrides(
 // static
 RefCountedMemory* ExtensionDOMUI::GetFaviconResourceBytes(Profile* profile,
                                                           GURL page_url) {
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI)) << "The extension "
+      "objects should only be accessed on the UI thread.";
+
   // Even when the extensions service is enabled by default, it's still
   // disabled in incognito mode.
   ExtensionsService* service = profile->GetExtensionsService();