Revert 186627

ui/compositor/compositor.h

Index: ui/compositor/compositor.h
===================================================================
--- ui/compositor/compositor.h	(revision 186756)
+++ ui/compositor/compositor.h	(working copy)
@@ -35,10 +35,6 @@
 class Rect;
 }
 
-namespace gpu {
-struct Mailbox;
-}
-
 namespace WebKit {
 class WebGraphicsContext3D;
 }
@@ -132,12 +128,12 @@
   virtual WebKit::WebGraphicsContext3D* HostContext3D() = 0;
 
   // Replaces the texture with the texture from the specified mailbox.
-  virtual void Consume(const gpu::Mailbox& mailbox_name,
+  virtual void Consume(const std::string& mailbox_name,
                        const gfx::Size& new_size) {}
 
   // Moves the texture into the mailbox and returns the mailbox name.
   // The texture must have been previously consumed from a mailbox.
-  virtual gpu::Mailbox Produce();
+  virtual std::string Produce();
 
  protected:
   virtual ~Texture();