Use std::string instead of WTF::String / TextStream

cc/CCSchedulerStateMachine.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CCSchedulerStateMachine_h
 #define CCSchedulerStateMachine_h
 
+#include <string>
 #include <wtf/Noncopyable.h>
-#include <wtf/text/WTFString.h>
 
 namespace WebCore {
 
 // The CCSchedulerStateMachine decides how to coordinate main thread activites
 // like painting/running javascript with rendering and input activities on the
 // impl thread.
 //
 // The state machine tracks internal state but is also influenced by external state.
 // Internal state includes things like whether a frame has been requested, while
 // external state includes things like the current time being near to the vblank time.
@@ skipping 102 matching lines @@
     // canDraw can be used to supress flashes or checkerboarding
     // when such behavior would be undesirable.
     void setCanDraw(bool can) { m_canDraw = can; }
 
     void didLoseContext();
     void didRecreateContext();
 
     // Exposed for testing purposes.
     void setMaximumNumberOfFailedDrawsBeforeDrawIsForced(int);
 
-    String toString();
+    std::string toString();
 
 protected:
     bool shouldDrawForced() const;
     bool drawSuspendedUntilCommit() const;
     bool scheduledToDraw() const;
     bool shouldDraw() const;
     bool shouldAcquireLayerTexturesForMainThread() const;
     bool hasDrawnThisFrame() const;
 
     CommitState m_commitState;
@@ skipping 14 matching lines @@
     bool m_canBeginFrame;
     bool m_canDraw;
     bool m_drawIfPossibleFailed;
     TextureState m_textureState;
     ContextState m_contextState;
 };
 
 }
 
 #endif // CCSchedulerStateMachine_h