Revert of Implement scroll handler latency tracking

cc/base/latency_info_swap_promise_monitor.cc

Index: cc/base/latency_info_swap_promise_monitor.cc
diff --git a/cc/base/latency_info_swap_promise_monitor.cc b/cc/base/latency_info_swap_promise_monitor.cc
index f724d6c05b78b3abbc984e34871fa77b4a059f33..0f2ff7481bb33f86393d754e8fb149d29fdd2b01 100644
--- a/cc/base/latency_info_swap_promise_monitor.cc
+++ b/cc/base/latency_info_swap_promise_monitor.cc
@@ -4,37 +4,10 @@
 
 #include "cc/base/latency_info_swap_promise_monitor.h"
 
-#include "base/threading/platform_thread.h"
 #include "cc/base/latency_info_swap_promise.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/layer_tree_host_impl.h"
 #include "cc/trees/layer_tree_impl.h"
-
-namespace {
-
-bool AddRenderingScheduledComponent(ui::LatencyInfo* latency_info) {
-  if (latency_info->FindLatency(
-          ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_COMPONENT, 0, NULL))
-    return false;
-  latency_info->AddLatencyNumber(
-      ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_COMPONENT, 0, 0);
-  return true;
-}
-
-bool AddForwardingScrollUpdateToMainComponent(ui::LatencyInfo* latency_info) {
-  if (latency_info->FindLatency(
-          ui::INPUT_EVENT_LATENCY_FORWARD_SCROLL_UPDATE_TO_MAIN_COMPONENT,
-          0,
-          NULL))
-    return false;
-  latency_info->AddLatencyNumber(
-      ui::INPUT_EVENT_LATENCY_FORWARD_SCROLL_UPDATE_TO_MAIN_COMPONENT,
-      0,
-      latency_info->trace_id);
-  return true;
-}
-
-}  // namespace
 
 namespace cc {
 
@@ -48,50 +21,23 @@
 LatencyInfoSwapPromiseMonitor::~LatencyInfoSwapPromiseMonitor() {}
 
 void LatencyInfoSwapPromiseMonitor::OnSetNeedsCommitOnMain() {
-  if (AddRenderingScheduledComponent(latency_)) {
+  if (!latency_->FindLatency(
+          ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_COMPONENT, 0, 0)) {
+    latency_->AddLatencyNumber(
+        ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_COMPONENT, 0, 0);
     scoped_ptr<SwapPromise> swap_promise(new LatencyInfoSwapPromise(*latency_));
     layer_tree_host_->QueueSwapPromise(swap_promise.Pass());
   }
 }
 
 void LatencyInfoSwapPromiseMonitor::OnSetNeedsRedrawOnImpl() {
-  if (AddRenderingScheduledComponent(latency_)) {
+  if (!latency_->FindLatency(
+          ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_COMPONENT, 0, 0)) {
+    latency_->AddLatencyNumber(
+        ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_COMPONENT, 0, 0);
     scoped_ptr<SwapPromise> swap_promise(new LatencyInfoSwapPromise(*latency_));
     layer_tree_host_impl_->active_tree()->QueueSwapPromise(swap_promise.Pass());
   }
 }
 
-void LatencyInfoSwapPromiseMonitor::OnForwardScrollUpdateToMainThreadOnImpl() {
-  if (AddForwardingScrollUpdateToMainComponent(latency_)) {
-    int64 new_sequence_number = 0;
-    for (ui::LatencyInfo::LatencyMap::const_iterator it =
-             latency_->latency_components.begin();
-         it != latency_->latency_components.end();
-         ++it) {
-      if (it->first.first == ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT) {
-        new_sequence_number =
-            (static_cast<int64>(base::PlatformThread::CurrentId()) << 32) |
-            (it->second.sequence_number & 0xffffffff);
-        DCHECK(new_sequence_number != it->second.sequence_number);
-        break;
-      }
-    }
-    if (!new_sequence_number)
-      return;
-    ui::LatencyInfo new_latency;
-    new_latency.AddLatencyNumber(
-        ui::INPUT_EVENT_LATENCY_BEGIN_SCROLL_UPDATE_MAIN_COMPONENT,
-        0,
-        new_sequence_number);
-    new_latency.TraceEventType("ScrollUpdate");
-    new_latency.CopyLatencyFrom(
-        *latency_,
-        ui::INPUT_EVENT_LATENCY_FORWARD_SCROLL_UPDATE_TO_MAIN_COMPONENT);
-    scoped_ptr<SwapPromise> swap_promise(
-        new LatencyInfoSwapPromise(new_latency));
-    layer_tree_host_impl_->QueueSwapPromiseForMainThreadScrollUpdate(
-        swap_promise.Pass());
-  }
-}
-
 }  // namespace cc