Splitting DidSwap in cc::SwapPromise into WillSwap and DidSwap

cc/layers/surface_layer.cc

Index: cc/layers/surface_layer.cc
diff --git a/cc/layers/surface_layer.cc b/cc/layers/surface_layer.cc
index 0f8bd3380be1aa873bf5ed197dcafabad45a9c51..61704b172c4c4b182afb55930df4bd9adaf3deb7 100644
--- a/cc/layers/surface_layer.cc
+++ b/cc/layers/surface_layer.cc
@@ -26,9 +26,10 @@ class SatisfySwapPromise : public SwapPromise {
 
  private:
   void DidActivate() override {}
-  void DidSwap(CompositorFrameMetadata* metadata) override {
+  void WillSwap(CompositorFrameMetadata* metadata) override {
     metadata->satisfies_sequences.push_back(sequence_.sequence);
   }
+  void DidSwap() override {}
 
   DidNotSwapAction DidNotSwap(DidNotSwapReason reason) override {
     satisfy_callback_.Run(sequence_);