Script streaming: stream async scripts too.

Source/core/dom/ScriptLoader.cpp

Index: Source/core/dom/ScriptLoader.cpp
diff --git a/Source/core/dom/ScriptLoader.cpp b/Source/core/dom/ScriptLoader.cpp
index d61dc554b2e9ede8904da6599b899db21e0375ad..d76b534a8015f92adbf66f5498ed7518efd12d40 100644
--- a/Source/core/dom/ScriptLoader.cpp
+++ b/Source/core/dom/ScriptLoader.cpp
@@ -253,6 +253,10 @@ bool ScriptLoader::prepareScript(const TextPosition& scriptStartPosition, Legacy
         m_pendingScript.watchForLoad(this);
     } else if (client->hasSourceAttribute()) {
         m_pendingScript = PendingScript(m_element, m_resource.get());
+        LocalFrame* frame = m_element->document().frame();
+        if (frame) {
+            ScriptStreamer::startStreaming(m_pendingScript, frame->settings(), ScriptState::forMainWorld(frame), PendingScript::Async);
+        }
         contextDocument->scriptRunner()->queueScriptForExecution(this, ScriptRunner::ASYNC_EXECUTION);
         // Note that watchForLoad can immediately call notifyFinished.
         m_pendingScript.watchForLoad(this);