Reland "Prepare blink to unify definitions of load completion"

Source/bindings/core/v8/ScriptController.cpp

Index: Source/bindings/core/v8/ScriptController.cpp
diff --git a/Source/bindings/core/v8/ScriptController.cpp b/Source/bindings/core/v8/ScriptController.cpp
index a3facd5591849c838d7082b9da36c08d51a2ab1f..2e3a2a9584739aa0bb6ce813acbde7601f2a690a 100644
--- a/Source/bindings/core/v8/ScriptController.cpp
+++ b/Source/bindings/core/v8/ScriptController.cpp
@@ -66,6 +66,7 @@
 #include "core/loader/DocumentLoader.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
+#include "core/loader/ProgressTracker.h"
 #include "core/plugins/PluginView.h"
 #include "platform/NotImplemented.h"
 #include "platform/TraceEvent.h"
@@ -542,6 +543,9 @@ bool ScriptController::executeScriptIfJavaScriptURL(const KURL& url)
         || !m_frame->document()->contentSecurityPolicy()->allowJavaScriptURLs(m_frame->document()->url(), eventHandlerPosition().m_line))
         return true;
 
+    if (m_frame->loader().stateMachine()->isDisplayingInitialEmptyDocument())
+        m_frame->loader().progress().progressStarted();
+
     // We need to hold onto the LocalFrame here because executing script can
     // destroy the frame.
     RefPtrWillBeRawPtr<LocalFrame> protect(m_frame.get());