cc: Introduce embedded_surfaces in metadata for surface Ids in draw quads

cc/ipc/struct_traits_unittest.cc

Index: cc/ipc/struct_traits_unittest.cc
diff --git a/cc/ipc/struct_traits_unittest.cc b/cc/ipc/struct_traits_unittest.cc
index 5115809c3b6a60b98d56f813297ba821940441e3..d132d29b7bb0a046093e87b52e8815e60bb10bab 100644
--- a/cc/ipc/struct_traits_unittest.cc
+++ b/cc/ipc/struct_traits_unittest.cc
@@ -374,6 +374,10 @@ TEST_F(StructTraitsTest, CompositorFrameMetadata) {
   SurfaceId id(FrameSinkId(1234, 4321),
                LocalSurfaceId(5678, base::UnguessableToken::Create()));
   referenced_surfaces.push_back(id);
+  std::vector<SurfaceId> embedded_surfaces;
+  SurfaceId id2(FrameSinkId(4321, 1234),
+                LocalSurfaceId(8765, base::UnguessableToken::Create()));
+  embedded_surfaces.push_back(id2);
   uint32_t frame_token = 0xdeadbeef;
 
   CompositorFrameMetadata input;
@@ -397,6 +401,7 @@ TEST_F(StructTraitsTest, CompositorFrameMetadata) {
   input.selection = selection;
   input.latency_info = latency_infos;
   input.referenced_surfaces = referenced_surfaces;
+  input.embedded_surfaces = embedded_surfaces;
   input.frame_token = frame_token;
 
   mojom::TraitsTestServicePtr proxy = GetTraitsTestProxy();
@@ -429,6 +434,9 @@ TEST_F(StructTraitsTest, CompositorFrameMetadata) {
   EXPECT_EQ(referenced_surfaces.size(), output.referenced_surfaces.size());
   for (uint32_t i = 0; i < referenced_surfaces.size(); ++i)
     EXPECT_EQ(referenced_surfaces[i], output.referenced_surfaces[i]);
+  EXPECT_EQ(embedded_surfaces.size(), output.embedded_surfaces.size());
+  for (uint32_t i = 0; i < embedded_surfaces.size(); ++i)
+    EXPECT_EQ(embedded_surfaces[i], output.embedded_surfaces[i]);
   EXPECT_EQ(frame_token, output.frame_token);
 }