Make debugger unloading deferred operation

src/debug.cc

 // 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 2363 matching lines @@
       ProcessCommand(Vector<const uint16_t>::empty());
     }
   }
 }
 
 
 void Debugger::ListenersChanged() {
   if (IsDebuggerActive()) {
     // Disable the compilation cache when the debugger is active.
     CompilationCache::Disable();
+    debugger_unload_pending_ = false;
   } else {
     CompilationCache::Enable();
-
     // Unload the debugger if event listener and message handler cleared.
-    if (Debug::InDebugger()) {
-      // If we are in debugger set the flag to unload the debugger when last
-      // EnterDebugger on the current stack is destroyed.
-      debugger_unload_pending_ = true;
-    } else {
-      UnloadDebugger();
-    }
+    // Schedule this for later, because we may be in non-V8 thread.
+    debugger_unload_pending_ = true;
   }
 }
 
 
 void Debugger::SetHostDispatchHandler(v8::Debug::HostDispatchHandler handler,
                                       int period) {
   host_dispatch_handler_ = handler;
   host_dispatch_micros_ = period * 1000;
 }
 
@@ skipping 339 matching lines @@
 
 
 void LockingCommandMessageQueue::Clear() {
   ScopedLock sl(lock_);
   queue_.Clear();
 }
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 } }  // namespace v8::internal