Turn libplatform into a component

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 "include/libplatform/libplatform.h"
 #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 {
 
 
@@ skipping 200 matching lines @@
     tracing::TracingController* tracing_controller) {
   tracing_controller_ = tracing_controller;
 }
 
 size_t DefaultPlatform::NumberOfAvailableBackgroundThreads() {
   return static_cast<size_t>(thread_pool_size_);
 }
 
 }  // namespace platform
 }  // namespace v8