Compositor thread plumbing for layout rectangle debug info.

cc/layers/layer_client.h

Index: cc/layers/layer_client.h
diff --git a/cc/layers/layer_client.h b/cc/layers/layer_client.h
index 73c0fd2514b3081a524c5704552f17790d71a8f0..6ef6efe1c1bee68efece9dd84315749a4805113a 100644
--- a/cc/layers/layer_client.h
+++ b/cc/layers/layer_client.h
@@ -7,14 +7,27 @@
 
 #include <string>
 
+#include "base/memory/ref_counted.h"
 #include "cc/base/cc_export.h"
 
+namespace base {
+namespace debug {
+class ConvertableToTraceFormat;
+}
+}
+
 namespace cc {
 
 class CC_EXPORT LayerClient {
  public:
   virtual std::string DebugName() = 0;
 
+  // Returns a pointer to a debug info object, if one has been computed.
+  // If not, returns NULL. If the returned pointer is non-NULL, the caller takes
+  // ownership of the pointer.
+  virtual scoped_refptr<base::debug::ConvertableToTraceFormat>
+      TakeDebugInfo() = 0;
+
  protected:
   virtual ~LayerClient() {}
 };