Remove LatencyInfo::sequence_number. (May break metrics).

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 93446c65df306cd657de6e7ff4f0d2d4d0ee763d..88963de5b22abff4d3b4ea7236f723daa6b7e900 100644
--- a/cc/ipc/struct_traits_unittest.cc
+++ b/cc/ipc/struct_traits_unittest.cc
@@ -361,7 +361,7 @@ TEST_F(StructTraitsTest, CompositorFrameMetadata) {
   selection.end.set_type(gfx::SelectionBound::RIGHT);
   ui::LatencyInfo latency_info;
   latency_info.AddLatencyNumber(
-      ui::LATENCY_BEGIN_SCROLL_LISTENER_UPDATE_MAIN_COMPONENT, 1337, 7331);
+      ui::LATENCY_BEGIN_SCROLL_LISTENER_UPDATE_MAIN_COMPONENT, 1337);
   std::vector<ui::LatencyInfo> latency_infos = {latency_info};
   std::vector<SurfaceId> referenced_surfaces;
   SurfaceId id(FrameSinkId(1234, 4321),
@@ -425,7 +425,6 @@ TEST_F(StructTraitsTest, CompositorFrameMetadata) {
   EXPECT_TRUE(output.latency_info[0].FindLatency(
       ui::LATENCY_BEGIN_SCROLL_LISTENER_UPDATE_MAIN_COMPONENT, 1337,
       &component));
-  EXPECT_EQ(7331, component.sequence_number);
   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]);