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 dc5d9cbe56c97eecdeab77266cb1e704533e3ca1..0dad777eb55ab267a05e43bfc54d74a3867c4426 100644
--- a/cc/ipc/struct_traits_unittest.cc
+++ b/cc/ipc/struct_traits_unittest.cc
@@ -364,7 +364,7 @@ TEST_F(StructTraitsTest, CompositorFrameMetadata) {
   ui::LatencyInfo latency_info;
   latency_info.set_trace_id(5);
   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),
@@ -428,7 +428,6 @@ 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]);