Remove static thread pointers from CC

cc/font_atlas.h

Index: cc/font_atlas.h
diff --git a/cc/font_atlas.h b/cc/font_atlas.h
index f9baea14fc2b8963457cd728e3052c11c28bbb24..5b9e3a9b5325fe622ecf050643da0f5495deae83 100644
--- a/cc/font_atlas.h
+++ b/cc/font_atlas.h
@@ -9,6 +9,7 @@
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/threading/thread_checker.h"
 #include "IntRect.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 
@@ -55,6 +56,8 @@ private:
 
     int m_fontHeight;
 
+    base::ThreadChecker m_threadChecker;
+
     DISALLOW_COPY_AND_ASSIGN(FontAtlas);
 };