Making AsyncInvoker destructor thread-safe.

webrtc/base/asyncinvoker.h

Index: webrtc/base/asyncinvoker.h
diff --git a/webrtc/base/asyncinvoker.h b/webrtc/base/asyncinvoker.h
index d91e30601eff620aaec65537ee47632187a705c5..5a14049494f1c7b06c9ff754b4f61caaccb1a708 100644
--- a/webrtc/base/asyncinvoker.h
+++ b/webrtc/base/asyncinvoker.h
@@ -14,8 +14,8 @@
 #include "webrtc/base/asyncinvoker-inl.h"
 #include "webrtc/base/bind.h"
 #include "webrtc/base/constructormagic.h"
+#include "webrtc/base/event.h"
 #include "webrtc/base/sigslot.h"
-#include "webrtc/base/scopedptrcollection.h"
 #include "webrtc/base/thread.h"
 
 namespace rtc {
@@ -80,7 +80,8 @@ class AsyncInvoker : public MessageHandler {
                    const FunctorT& functor,
                    uint32_t id = 0) {
     scoped_refptr<AsyncClosure> closure(
-        new RefCountedObject<FireAndForgetAsyncClosure<FunctorT> >(functor));
+        new RefCountedObject<FireAndForgetAsyncClosure<FunctorT> >(this,
+                                                                   functor));
     DoInvoke(posted_from, thread, closure, id);
   }
 
@@ -93,7 +94,8 @@ class AsyncInvoker : public MessageHandler {
                           uint32_t delay_ms,
                           uint32_t id = 0) {
     scoped_refptr<AsyncClosure> closure(
-        new RefCountedObject<FireAndForgetAsyncClosure<FunctorT> >(functor));
+        new RefCountedObject<FireAndForgetAsyncClosure<FunctorT> >(this,
+                                                                   functor));
     DoInvokeDelayed(posted_from, thread, closure, delay_ms, id);
   }
 
@@ -155,7 +157,10 @@ class AsyncInvoker : public MessageHandler {
                        const scoped_refptr<AsyncClosure>& closure,
                        uint32_t delay_ms,
                        uint32_t id);
-  bool destroying_;
+  volatile int pending_invocations_ = 0;
+  Event invocation_complete_;
+  bool destroying_ = false;
+  friend class AsyncClosure;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(AsyncInvoker);
 };