Add MonotonicallyIncreasingTime to V8 Platform.

src/libplatform/default-platform.cc

 // Copyright 2013 the V8 project 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 "src/libplatform/default-platform.h"
 
 #include <algorithm>
 #include <queue>
 
 #include "src/base/logging.h"
 #include "src/base/platform/platform.h"
+#include "src/base/platform/time.h"
 #include "src/base/sys-info.h"
 #include "src/libplatform/worker-thread.h"
 
 namespace v8 {
 namespace platform {
 
 
 v8::Platform* CreateDefaultPlatform(int thread_pool_size) {
   DefaultPlatform* platform = new DefaultPlatform();
   platform->SetThreadPoolSize(thread_pool_size);
@@ skipping 77 matching lines @@
   EnsureInitialized();
   queue_.Append(task);
 }
 
 
 void DefaultPlatform::CallOnForegroundThread(v8::Isolate* isolate, Task* task) {
   base::LockGuard<base::Mutex> guard(&lock_);
   main_thread_queue_[isolate].push(task);
 }
 
+
+double DefaultPlatform::MonotonicallyIncreasingTime() {
+  return base::TimeTicks::HighResolutionNow().ToInternalValue() /
+         static_cast<double>(base::Time::kMicrosecondsPerSecond);
+}
 } }  // namespace v8::platform