Fix login visual hitch on chromebook

chrome/browser/ui/app_list/search_builder.cc

Index: chrome/browser/ui/app_list/search_builder.cc
diff --git a/chrome/browser/ui/app_list/search_builder.cc b/chrome/browser/ui/app_list/search_builder.cc
index d635180a007b94764840e1e0e194eca8d68772e4..c9813849ae9529eceafbc0eda711cc9621b346ea 100644
--- a/chrome/browser/ui/app_list/search_builder.cc
+++ b/chrome/browser/ui/app_list/search_builder.cc
@@ -254,6 +254,7 @@ class ContactResult : public SearchBuilderResult,
  protected:
   // Overridden from SearchBuilderResult:
   virtual void UpdateIcon() OVERRIDE {
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
     const contacts::Contact* contact = GetContact();
     if (contact && contact->has_raw_untrusted_photo()) {
       photo_decoder_ =
@@ -261,7 +262,9 @@ class ContactResult : public SearchBuilderResult,
               this,
               contact->raw_untrusted_photo(),
               ImageDecoder::DEFAULT_CODEC);
-      photo_decoder_->Start();
+      scoped_refptr<base::MessageLoopProxy> task_runner =
+          BrowserThread::GetMessageLoopProxyForThread(BrowserThread::UI);
+      photo_decoder_->Start(task_runner);
     } else {
       SetIcon(
           *ui::ResourceBundle::GetSharedInstance().GetImageSkiaNamed(