Remove static thread pointers from CC

cc/prioritized_texture.h

Index: cc/prioritized_texture.h
diff --git a/cc/prioritized_texture.h b/cc/prioritized_texture.h
index f8c7240c9c70430d94cdc8634dc89df352406b86..2763fc470da640a5ca9afb6dd5c89113fe168bcb 100644
--- a/cc/prioritized_texture.h
+++ b/cc/prioritized_texture.h
@@ -20,6 +20,7 @@
 namespace cc {
 
 class PrioritizedTextureManager;
+class Proxy;
 
 class CC_EXPORT PrioritizedTexture {
 public:
@@ -108,6 +109,8 @@ private:
         bool resourceHasBeenDeleted() const;
 
     private:
+        const Proxy* proxy() const;
+
         friend class PrioritizedTexture;
         PrioritizedTexture* m_owner;
         int m_priorityAtLastPriorityUpdate;
@@ -120,7 +123,6 @@ private:
 #ifndef NDEBUG
         ResourceProvider* m_resourceProvider;
 #endif
-
         DISALLOW_COPY_AND_ASSIGN(Backing);
     };