Move platform abstraction to base library

src/log.h

 // Copyright 2012 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.
 
 #ifndef V8_LOG_H_
 #define V8_LOG_H_
 
 #include <string>
 
 #include "src/allocation.h"
+#include "src/base/platform/elapsed-timer.h"
+#include "src/base/platform/platform.h"
 #include "src/objects.h"
-#include "src/platform.h"
-#include "src/platform/elapsed-timer.h"
 
 namespace v8 {
+
+namespace base {
+class Semaphore;
+}
+
 namespace internal {
 
 // Logger is used for collecting logging information from V8 during
 // execution. The result is dumped to a file.
 //
 // Available command line flags:
 //
 //  --log
 // Minimal logging (no API, code, or GC sample events), default is off.
 //
@@ skipping 24 matching lines @@
 // tick profiler requires code events, so --prof implies --log-code.
 
 // Forward declarations.
 class CodeEventListener;
 class CompilationInfo;
 class CpuProfiler;
 class Isolate;
 class Log;
 class PositionsRecorder;
 class Profiler;
-class Semaphore;
 class Ticker;
 struct TickSample;
 
 #undef LOG
 #define LOG(isolate, Call)                          \
   do {                                              \
     v8::internal::Logger* logger =                  \
         (isolate)->logger();                        \
     if (logger->is_logging())                       \
       logger->Call;                                 \
@@ skipping 358 matching lines @@
   PerfBasicLogger* perf_basic_logger_;
   PerfJitLogger* perf_jit_logger_;
   LowLevelLogger* ll_logger_;
   JitLogger* jit_logger_;
   List<CodeEventListener*> listeners_;
 
   // Guards against multiple calls to TearDown() that can happen in some tests.
   // 'true' between SetUp() and TearDown().
   bool is_initialized_;
 
-  ElapsedTimer timer_;
+  base::ElapsedTimer timer_;
 
   friend class CpuProfiler;
 };
 
 
 class CodeEventListener {
  public:
   virtual ~CodeEventListener() {}
 
   virtual void CodeCreateEvent(Logger::LogEventsAndTags tag,
@@ skipping 70 matching lines @@
                                  int length) = 0;
 
   NameBuffer* name_buffer_;
 };
 
 
 } }  // namespace v8::internal
 
 
 #endif  // V8_LOG_H_