Merge r8833 "Minimize malloc heap allocation on process startup" to 3.2.

src/debug.h

 // Copyright 2006-2008 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 791 matching lines @@
   void set_compiling_natives(bool compiling_natives) {
     Debugger::compiling_natives_ = compiling_natives;
   }
   bool compiling_natives() const { return compiling_natives_; }
   void set_loading_debugger(bool v) { is_loading_debugger_ = v; }
   bool is_loading_debugger() const { return is_loading_debugger_; }
 
   bool IsDebuggerActive();
 
  private:
-  Debugger();
+  explicit Debugger(Isolate* isolate);
 
   void CallEventCallback(v8::DebugEvent event,
                          Handle<Object> exec_state,
                          Handle<Object> event_data,
                          v8::Debug::ClientData* client_data);
   void CallCEventCallback(v8::DebugEvent event,
                           Handle<Object> exec_state,
                           Handle<Object> event_data,
                           v8::Debug::ClientData* client_data);
   void CallJSEventCallback(v8::DebugEvent event,
@@ skipping 223 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(MessageDispatchHelperThread);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 #endif  // V8_DEBUG_H_