Revert of Fixing potential AsyncInvoker deadlock that occurs for "reentrant" invocations.

webrtc/base/asyncinvoker-inl.h

Index: webrtc/base/asyncinvoker-inl.h
diff --git a/webrtc/base/asyncinvoker-inl.h b/webrtc/base/asyncinvoker-inl.h
index a1c2c8e0cf6591f6c80a0dc0b480f483be39de1f..5f7cd4959a07e695ee9d526b31f641240aa33862 100644
--- a/webrtc/base/asyncinvoker-inl.h
+++ b/webrtc/base/asyncinvoker-inl.h
@@ -27,7 +27,7 @@
 // on the calling thread if necessary.
 class AsyncClosure {
  public:
-  explicit AsyncClosure(AsyncInvoker* invoker);
+  explicit AsyncClosure(AsyncInvoker* invoker) : invoker_(invoker) {}
   virtual ~AsyncClosure();
   // Runs the asynchronous task, and triggers a callback to the calling
   // thread if needed. Should be called from the target thread.