Initialize webkit thread asynchronously

content/browser/in_process_webkit/webkit_thread.cc

Index: content/browser/in_process_webkit/webkit_thread.cc
diff --git a/content/browser/in_process_webkit/webkit_thread.cc b/content/browser/in_process_webkit/webkit_thread.cc
index 072a1bb2f83a855dd7aba748738988fe3f35a282..26b8751966bdbd03245511e59221ea9b5e4d9c59 100644
--- a/content/browser/in_process_webkit/webkit_thread.cc
+++ b/content/browser/in_process_webkit/webkit_thread.cc
@@ -13,6 +13,27 @@
 
 using content::BrowserThread;
 
+// Must be private so that we can carefully control its lifetime. Cannot be
+// anonymous as it is forward-declared in the .h.
+class InternalWebKitThread : public content::BrowserThreadImpl {
+ public:
+  InternalWebKitThread();
+  virtual ~InternalWebKitThread();
+  // Does the actual initialization and shutdown of WebKit.
+  void AsyncInit();
+
+  virtual void Init();
+  virtual void CleanUp();
+
+ private:
+  // The WebKitPlatformSupport implementation.  Only access on WebKit thread.
+  scoped_ptr<BrowserWebKitPlatformSupportImpl> webkit_platform_support_;
+};
+
+// Only used as a parameter in a task sent to itself, so ref-counting
+// is not needed.
+DISABLE_RUNNABLE_METHOD_REFCOUNT(InternalWebKitThread);
+
 WebKitThread::WebKitThread() {
 }
 
@@ -36,17 +57,20 @@ void WebKitThread::Initialize() {
   webkit_thread_.reset(new InternalWebKitThread);
   bool started = webkit_thread_->Start();
   DCHECK(started);
+  BrowserThread::PostTask(BrowserThread::WEBKIT, FROM_HERE, NewRunnableMethod(
+      webkit_thread_.get(),
+      &InternalWebKitThread::AsyncInit));
 }
 
-WebKitThread::InternalWebKitThread::InternalWebKitThread()
+InternalWebKitThread::InternalWebKitThread()
     : content::BrowserThreadImpl(BrowserThread::WEBKIT) {
 }
 
-WebKitThread::InternalWebKitThread::~InternalWebKitThread() {
+InternalWebKitThread::~InternalWebKitThread() {
   Stop();
 }
 
-void WebKitThread::InternalWebKitThread::Init() {
+void InternalWebKitThread::AsyncInit() {
   DCHECK(!webkit_platform_support_.get());
   webkit_platform_support_.reset(new BrowserWebKitPlatformSupportImpl);
   WebKit::initializeWithoutV8(webkit_platform_support_.get());
@@ -57,12 +81,14 @@ void WebKitThread::InternalWebKitThread::Init() {
   // TODO(michaeln): remove this when the following is landed.
   // https://bugs.webkit.org/show_bug.cgi?id=61145
   WebKit::WebSecurityOrigin::create(GURL("http://chromium.org"));
+}
 
-  // If possible, post initialization tasks to this thread (rather than doing
-  // them now) so we don't block the UI thread any longer than we have to.
+void InternalWebKitThread::Init() {
+  // Any work done here blocks the caller; as WebKit::initialize... takes time
+  // to complete we do it in the cutom async variant above instead.
 }
 
-void WebKitThread::InternalWebKitThread::CleanUp() {
+void InternalWebKitThread::CleanUp() {
   DCHECK(webkit_platform_support_.get());
   WebKit::shutdown();
 }