Clean up VMState a little bit.

src/log.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 145 matching lines @@
 class Logger {
  public:
 #define DECLARE_ENUM(enum_item, ignore) enum_item,
   enum LogEventsAndTags {
     LOG_EVENTS_AND_TAGS_LIST(DECLARE_ENUM)
     NUMBER_OF_LOG_EVENTS
   };
 #undef DECLARE_ENUM
 
   // Acquires resources for logging if the right flags are set.
-  bool SetUp();
+  bool SetUp(Isolate* isolate);
 
   // Sets the current code event handler.
   void SetCodeEventHandler(uint32_t options,
                            JitCodeEventHandler event_handler);
 
   Sampler* sampler();
 
   // Frees resources acquired in SetUp.
   // When a temporary file is used for the log, returns its stream descriptor,
   // leaving the file open.
@@ skipping 108 matching lines @@
                           uintptr_t end);
   void SharedLibraryEvent(const wchar_t* library_path,
                           uintptr_t start,
                           uintptr_t end);
 
   // ==== Events logged by --log-timer-events. ====
   enum StartEnd { START, END };
 
   void TimerEvent(StartEnd se, const char* name);
 
-  static void EnterExternal();
-  static void LeaveExternal();
+  static void EnterExternal(Isolate* isolate);
+  static void LeaveExternal(Isolate* isolate);
 
   class TimerEventScope {
    public:
     TimerEventScope(Isolate* isolate, const char* name)
         : isolate_(isolate), name_(name) {
       if (FLAG_log_internal_timer_events) LogTimerEvent(START);
     }
 
     ~TimerEventScope() {
       if (FLAG_log_internal_timer_events) LogTimerEvent(END);
@@ skipping 152 matching lines @@
   // An array of log events names.
   const char* const* log_events_;
 
   // Internal implementation classes with access to
   // private members.
   friend class EventLog;
   friend class Isolate;
   friend class LogMessageBuilder;
   friend class TimeLog;
   friend class Profiler;
-  friend class VMState;
+  template <StateTag Tag> friend class VMState;
 
   friend class LoggerTestHelper;
 
 
   int logging_nesting_;
   int cpu_profiler_nesting_;
 
   Log* log_;
 
   NameBuffer* name_buffer_;
@@ skipping 21 matching lines @@
   int64_t epoch_;
 
   friend class CpuProfiler;
 };
 
 
 } }  // namespace v8::internal
 
 
 #endif  // V8_LOG_H_