Convert ReadMessage...() to use the new user pointer handling (see r285350).

mojo/system/dispatcher.h

 // Copyright 2013 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 MOJO_SYSTEM_DISPATCHER_H_
 #define MOJO_SYSTEM_DISPATCHER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 69 matching lines @@
   // written; not that |this| must not be in |transports|. On success, all the
   // dispatchers in |transports| must have been moved to a closed state; on
   // failure, they should remain in their original state.
   MojoResult WriteMessage(const void* bytes,
                           uint32_t num_bytes,
                           std::vector<DispatcherTransport>* transports,
                           MojoWriteMessageFlags flags);
   // |dispatchers| must be non-null but empty, if |num_dispatchers| is non-null
   // and nonzero. On success, it will be set to the dispatchers to be received
   // (and assigned handles) as part of the message.
-  MojoResult ReadMessage(void* bytes,
-                         uint32_t* num_bytes,
+  MojoResult ReadMessage(UserPointer<void> bytes,
+                         UserPointer<uint32_t> num_bytes,
                          DispatcherVector* dispatchers,
                          uint32_t* num_dispatchers,
                          MojoReadMessageFlags flags);
   MojoResult WriteData(const void* elements,
                        uint32_t* elements_num_bytes,
                        MojoWriteDataFlags flags);
   MojoResult BeginWriteData(UserPointer<void*> buffer,
                             UserPointer<uint32_t> buffer_num_bytes,
                             MojoWriteDataFlags flags);
   MojoResult EndWriteData(uint32_t num_bytes_written);
@@ skipping 108 matching lines @@
 
   // These are to be overridden by subclasses (if necessary). They are never
   // called after the dispatcher has been closed. They are called under |lock_|.
   // See the descriptions of the methods without the "ImplNoLock" for more
   // information.
   virtual MojoResult WriteMessageImplNoLock(
       const void* bytes,
       uint32_t num_bytes,
       std::vector<DispatcherTransport>* transports,
       MojoWriteMessageFlags flags);
-  virtual MojoResult ReadMessageImplNoLock(void* bytes,
-                                           uint32_t* num_bytes,
+  virtual MojoResult ReadMessageImplNoLock(UserPointer<void> bytes,
+                                           UserPointer<uint32_t> num_bytes,
                                            DispatcherVector* dispatchers,
                                            uint32_t* num_dispatchers,
                                            MojoReadMessageFlags flags);
   virtual MojoResult WriteDataImplNoLock(const void* elements,
                                          uint32_t* num_bytes,
                                          MojoWriteDataFlags flags);
   virtual MojoResult BeginWriteDataImplNoLock(
       UserPointer<void*> buffer,
       UserPointer<uint32_t> buffer_num_bytes,
       MojoWriteDataFlags flags);
@@ skipping 141 matching lines @@
 
   Dispatcher* dispatcher_;
 
   // Copy and assign allowed.
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_SYSTEM_DISPATCHER_H_