Add a |scope| argument to TRACE_EVENT_INSTANT* and require its presence.

chrome/test/perf/rendering/latency_tests.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "base/stringprintf.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 641 matching lines @@
   mouse_event.movementX = 1;
   mouse_x_ += mouse_event.movementX;
   // Wrap mouse_x_ when it's near the edge of the tab.
   if (mouse_x_ > tab_width_ - 5)
     mouse_x_ = 1;
   mouse_event.x = mouse_event.windowX = mouse_x_;
   // Set y coordinate to be a few pixels down from the top of the window,
   // so that it is between the top and bottom of the canvas.
   mouse_event.y = mouse_event.windowY = 5;
   mouse_event.type = WebKit::WebInputEvent::MouseMove;
-  TRACE_EVENT_INSTANT1("test_latency", "MouseEventBegin", "x", mouse_x_);
+  TRACE_EVENT_INSTANT1("test_latency", "MouseEventBegin",
+                       TRACE_EVENT_SCOPE_THREAD, "x", mouse_x_);
   rvh->ForwardMouseEvent(mouse_event);
 }
 
 void LatencyTest::PrintEvents(const TraceEventVector& events) {
   bool is_software = (mode_ == kSoftware);
   int swap_count = 0;
   for (size_t i = 0; i < events.size(); ++i) {
     if (events[i]->name == "MouseEventBegin") {
       printf("%03d ", events[i]->GetKnownArgAsInt("x"));
     } else if (events[i]->name == "DoClear") {
@@ skipping 70 matching lines @@
     kInputHeavy | kInputDirty | kRafHeavy, \
     kInputHeavy | kInputDirty | kRafHeavy | kPaintHeavy, \
     kInputDirty | kPaintHeavy, \
     kInputDirty | kRafHeavy | kPaintHeavy)
 
 INSTANTIATE_TEST_CASE_P(, LatencyTestWebGL, LATENCY_SUITE_MODES());
 INSTANTIATE_TEST_CASE_P(, LatencyTestWebGLThread, LATENCY_SUITE_MODES());
 INSTANTIATE_TEST_CASE_P(, LatencyTestSW, LATENCY_SUITE_MODES());
 
 }  // namespace