[Isolates] Fix auto extraction of isolate from heap objects in handle constructor.

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 832 matching lines @@
 
 // This class is used for entering the debugger. Create an instance in the stack
 // to enter the debugger. This will set the current break state, make sure the
 // debugger is loaded and switch to the debugger context. If the debugger for
 // some reason could not be entered FailedToEnter will return true.
 class EnterDebugger BASE_EMBEDDED {
  public:
   EnterDebugger()
       : isolate_(Isolate::Current()),
         prev_(isolate_->debug()->debugger_entry()),
-        has_js_frames_(!it_.done()) {
+        has_js_frames_(!it_.done()),
+        save_(isolate_) {
     Debug* debug = isolate_->debug();
     ASSERT(prev_ != NULL || !debug->is_interrupt_pending(PREEMPT));
     ASSERT(prev_ != NULL || !debug->is_interrupt_pending(DEBUGBREAK));
 
     // Link recursive debugger entry.
     debug->set_debugger_entry(this);
 
     // Store the previous break id and frame id.
     break_id_ = debug->break_id();
     break_frame_id_ = debug->break_frame_id();
@@ skipping 167 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(MessageDispatchHelperThread);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 #endif  // V8_DEBUG_H_