Surfaces system timestamp in the blink platform interface.

content/child/blink_platform_impl.cc

 // Copyright 2014 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 "content/child/blink_platform_impl.h"
 
 #include <math.h>
 
 #include <vector>
 
@@ skipping 1031 matching lines @@
 
 double BlinkPlatformImpl::currentTime() {
   return base::Time::Now().ToDoubleT();
 }
 
 double BlinkPlatformImpl::monotonicallyIncreasingTime() {
   return base::TimeTicks::Now().ToInternalValue() /
       static_cast<double>(base::Time::kMicrosecondsPerSecond);
 }
 
+double BlinkPlatformImpl::systemTraceTime() {
+  return base::TimeTicks::NowFromSystemTraceTime().ToInternalValue() /
+      static_cast<double>(base::Time::kMicrosecondsPerSecond);
+}
+
 void BlinkPlatformImpl::cryptographicallyRandomValues(
     unsigned char* buffer, size_t length) {
   base::RandBytes(buffer, length);
 }
 
 void BlinkPlatformImpl::setSharedTimerFiredFunction(void (*func)()) {
   shared_timer_func_ = func;
 }
 
 void BlinkPlatformImpl::setSharedTimerFireInterval(
@@ skipping 273 matching lines @@
   return WebString::fromUTF8(ui::KeycodeConverter::DomCodeToCodeString(
       static_cast<ui::DomCode>(dom_code)));
 }
 
 int BlinkPlatformImpl::domEnumFromCodeString(const WebString& code) {
   return static_cast<int>(ui::KeycodeConverter::CodeStringToDomCode(
       code.utf8().data()));
 }
 
 }  // namespace content