cc: Unify use of DidSwapBuffers() and did_request_swap

cc/scheduler/draw_swap_readback_result.h

Index: cc/scheduler/draw_swap_readback_result.h
diff --git a/cc/scheduler/draw_swap_readback_result.h b/cc/scheduler/draw_swap_readback_result.h
index 852b89720a0d006bc4c0247887ae9d15a778eb13..de6b43bc512a9cd38fe8d9a5c5ec7b14a0f878de 100644
--- a/cc/scheduler/draw_swap_readback_result.h
+++ b/cc/scheduler/draw_swap_readback_result.h
@@ -7,8 +7,7 @@
 
 namespace cc {
 
-struct DrawSwapReadbackResult {
-  enum DrawResult {
+enum DrawResult {
     INVALID_RESULT,
     DRAW_SUCCESS,
     DRAW_ABORTED_CHECKERBOARD_ANIMATIONS,
@@ -16,21 +15,6 @@ struct DrawSwapReadbackResult {
     DRAW_ABORTED_CANT_READBACK,
     DRAW_ABORTED_CONTEXT_LOST,
     DRAW_ABORTED_CANT_DRAW,
-  };
-
-  DrawSwapReadbackResult()
-      : draw_result(INVALID_RESULT),
-        did_request_swap(false),
-        did_readback(false) {}
-  DrawSwapReadbackResult(DrawResult draw_result,
-                         bool did_request_swap,
-                         bool did_readback)
-      : draw_result(draw_result),
-        did_request_swap(did_request_swap),
-        did_readback(did_readback) {}
-  DrawResult draw_result;
-  bool did_request_swap;
-  bool did_readback;
 };
 
 }  // namespace cc