Use LatencyInfoSwapPromise to track LatencyInfo through compositor

cc/base/swap_promise.h

Index: cc/base/swap_promise.h
diff --git a/cc/base/swap_promise.h b/cc/base/swap_promise.h
index 90bf6af53a6a0909484cd897b1ccab6a2cbe3844..1d4c2473e5216d10bd2e78d174737b9d72b33124 100644
--- a/cc/base/swap_promise.h
+++ b/cc/base/swap_promise.h
@@ -5,6 +5,8 @@
 #ifndef CC_BASE_SWAP_PROMISE_H_
 #define CC_BASE_SWAP_PROMISE_H_
 
+#include "cc/output/compositor_frame_metadata.h"
+
 namespace cc {
 
 const unsigned int kMaxQueuedSwapPromiseNumber = 100;
@@ -29,8 +31,10 @@ const unsigned int kMaxQueuedSwapPromiseNumber = 100;
 // DidSwap() and DidNotSwap().
 class SwapPromise {
  public:
-  SwapPromise() {}
-  virtual ~SwapPromise() {}
+  enum SwapPromiseType {

[danakj, 2013/11/27 20:11:42]

This is no longer needed

[Yufeng Shen (Slow to review), 2013/11/27 20:18:52]

Done.

+    SWAP_PROMISE_UNKNOWN,
+    SWAP_PROMISE_LATENCY_INFO,
+  };
 
   enum DidNotSwapReason {
     DID_NOT_SWAP_UNKNOWN,
@@ -39,8 +43,18 @@ class SwapPromise {
     SWAP_PROMISE_LIST_OVERFLOW,
   };
 
-  virtual void DidSwap() = 0;
+  explicit SwapPromise(SwapPromiseType type) : type_(type) {}
+  virtual ~SwapPromise() {}
+
+  SwapPromiseType type() {
+    return type_;
+  }
+
+  virtual void DidSwap(CompositorFrameMetadata* metadata) = 0;
   virtual void DidNotSwap(DidNotSwapReason reason) = 0;
+
+ protected:
+  SwapPromiseType type_;

[danakj, 2013/11/27 20:11:42]

The type should be able to go away now.

[Yufeng Shen (Slow to review), 2013/11/27 20:18:52]

Done.

 };
 
 }  // namespace cc