Simplify setting lockBackForwardList() in NavigationScheduler.

Source/core/loader/FrameLoader.cpp

Index: Source/core/loader/FrameLoader.cpp
diff --git a/Source/core/loader/FrameLoader.cpp b/Source/core/loader/FrameLoader.cpp
index ffb0b020aa0a80bec72ddbb3e845367de87ca2eb..131dfc2f3998206815c019e2db50dcab9f89602d 100644
--- a/Source/core/loader/FrameLoader.cpp
+++ b/Source/core/loader/FrameLoader.cpp
@@ -292,6 +292,8 @@ void FrameLoader::clear(ClearOptions options)
 
     if (m_stateMachine.isDisplayingInitialEmptyDocument())
         m_stateMachine.advanceTo(FrameLoaderStateMachine::CommittedFirstRealLoad);
+    else if (!m_stateMachine.committedMultipleRealLoads())
+        m_stateMachine.advanceTo(FrameLoaderStateMachine::CommittedMultipleRealLoads);
 }
 
 void FrameLoader::receivedFirstData()
@@ -1298,8 +1300,7 @@ void FrameLoader::loadWithNavigationAction(const NavigationAction& action, Frame
         m_stateMachine.advanceTo(FrameLoaderStateMachine::StartedFirstRealLoad);
 
     // The current load should replace the history item if it is the first real
-    // load of the frame. FrameLoadTypeRedirectWithLockedBackForwardList is a
-    // proxy for history()->currentItemShouldBeReplaced().

[Nate Chapin, 2013/11/19 20:05:25]

This sentence wasn't accurate, and now it's obsolete, too.

+    // load of the frame.
     bool replacesCurrentHistoryItem = false;
     if (type == FrameLoadTypeRedirectWithLockedBackForwardList
         || !m_stateMachine.committedFirstRealDocumentLoad()) {