Remove obsolete methods from IPC::Channel and related classes.

ipc/ipc_channel.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef IPC_IPC_CHANNEL_H_
 #define IPC_IPC_CHANNEL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 210 matching lines @@
   // details.
   virtual void Flush();
 
   // Close this Channel explicitly.  May be called multiple times.
   // On POSIX calling close on an IPC channel that listens for connections will
   // cause it to close any accepted connections, and it will stop listening for
   // new connections. If you just want to close the currently accepted
   // connection and listen for new ones, use ResetToAcceptingConnectionState.
   virtual void Close() = 0;
 
-  // Get its own process id. This value is told to the peer.
-  virtual base::ProcessId GetSelfPID() const = 0;
-
   // Gets a helper for associating Mojo interfaces with this Channel.
   //
   // NOTE: Not all implementations support this.
   virtual AssociatedInterfaceSupport* GetAssociatedInterfaceSupport();
 
   // Overridden from ipc::Sender.
   // Send a message over the Channel to the listener on the other end.
   //
   // |message| must be allocated using operator new.  This object will be
   // deleted once the contents of the Message have been sent.
   bool Send(Message* message) override = 0;
 
-  // NaCl in Non-SFI mode runs on Linux directly, and the following functions
-  // compiled on Linux are also needed. Please see also comments in
-  // components/nacl_nonsfi.gyp for more details.
-#if defined(OS_POSIX) && !defined(OS_NACL_SFI)
-  // On POSIX an IPC::Channel wraps a socketpair(), this method returns the
-  // FD # for the client end of the socket.
-  // This method may only be called on the server side of a channel.
-  // This method can be called on any thread.
-  virtual int GetClientFileDescriptor() const = 0;
-
-  // Same as GetClientFileDescriptor, but transfers the ownership of the
-  // file descriptor to the caller.
-  // This method can be called on any thread.
-  virtual base::ScopedFD TakeClientFileDescriptor() = 0;
-#endif
-
 #if !defined(OS_NACL_SFI)
   // Generates a channel ID that's non-predictable and unique.
   static std::string GenerateUniqueRandomChannelID();
-
-  // Generates a channel ID that, if passed to the client as a shared secret,

[Tom Sepez, 2016/11/09 00:31:00]

This was used to avoid a fairly serious bug where a compromised process could
race the creation of a more privileged one, and squat on the end of its pipe. 
Remind me again of how we avoid this issue under mojo?

[Sam McNally, 2016/11/09 05:06:30]

In most cases, pipe names aren't used: for normal processes FDs/HANDLEs are
passed/inherited at launch. I'm not sure what we do for the named pipes used
with elevated processes.

-  // will validate that the client's authenticity. On platforms that do not
-  // require additional this is simply calls GenerateUniqueRandomChannelID().
-  // For portability the prefix should not include the \ character.
-  static std::string GenerateVerifiedChannelID(const std::string& prefix);
 #endif
 
   // Deprecated: Create a mojo::MessagePipe directly and release() its handles
   // instead.
   //
   // Generates a pair of channel handles that can be used as the client and
   // server ends of a ChannelMojo. |name_postfix| is ignored.
   static void GenerateMojoChannelHandlePair(
       const std::string& name_postfix,
       IPC::ChannelHandle* handle0,
@@ skipping 35 matching lines @@
   // of Connect().
   void WillConnect();
 
  private:
   bool did_start_connect_ = false;
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_CHANNEL_H_