Revert of Support early associated interface binding on ChannelMojo

ipc/ipc_message_pipe_reader.h

Index: ipc/ipc_message_pipe_reader.h
diff --git a/ipc/ipc_message_pipe_reader.h b/ipc/ipc_message_pipe_reader.h
index e6a2a137a0a39930266c1400977befb13d10c51a..5aec4407aaef45842c397d4402e846ba9f4dbd8c 100644
--- a/ipc/ipc_message_pipe_reader.h
+++ b/ipc/ipc_message_pipe_reader.h
@@ -13,7 +13,6 @@
 #include "base/atomicops.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
-#include "base/process/process_handle.h"
 #include "base/threading/thread_checker.h"
 #include "ipc/ipc.mojom.h"
 #include "ipc/ipc_export.h"
@@ -48,12 +47,26 @@
  public:
   class Delegate {
    public:
-    virtual void OnPeerPidReceived() = 0;
     virtual void OnMessageReceived(const Message& message) = 0;
     virtual void OnPipeError() = 0;
     virtual void OnAssociatedInterfaceRequest(
         const std::string& name,
         mojo::ScopedInterfaceEndpointHandle handle) = 0;
+  };
+
+  // Delay the object deletion using the current message loop.
+  // This is intended to used by MessagePipeReader owners.
+  class DelayedDeleter {
+   public:
+    typedef std::default_delete<MessagePipeReader> DefaultType;
+
+    static void DeleteNow(MessagePipeReader* ptr) { delete ptr; }
+
+    DelayedDeleter() {}
+    explicit DelayedDeleter(const DefaultType&) {}
+    DelayedDeleter& operator=(const DefaultType&) { return *this; }
+
+    void operator()(MessagePipeReader* ptr) const;
   };
 
   // Builds a reader that reads messages from |receive_handle| and lets
@@ -69,6 +82,7 @@
   MessagePipeReader(mojo::MessagePipeHandle pipe,
                     mojom::ChannelAssociatedPtr sender,
                     mojo::AssociatedInterfaceRequest<mojom::Channel> receiver,
+                    base::ProcessId peer_pid,
                     Delegate* delegate);
   ~MessagePipeReader() override;
 
@@ -94,7 +108,6 @@
 
  private:
   // mojom::Channel:
-  void SetPeerPid(int32_t peer_pid) override;
   void Receive(mojo::Array<uint8_t> data,
                mojo::Array<mojom::SerializedHandlePtr> handles) override;
   void GetAssociatedInterface(
@@ -103,7 +116,7 @@
 
   // |delegate_| is null once the message pipe is closed.
   Delegate* delegate_;
-  base::ProcessId peer_pid_ = base::kNullProcessId;
+  base::ProcessId peer_pid_;
   mojom::ChannelAssociatedPtr sender_;
   mojo::AssociatedBinding<mojom::Channel> binding_;