Convert WriteData...() 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 74 matching lines @@
                           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(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,
+  MojoResult WriteData(UserPointer<const void> elements,
+                       UserPointer<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);
   MojoResult ReadData(UserPointer<void> elements,
                       UserPointer<uint32_t> num_bytes,
                       MojoReadDataFlags flags);
   MojoResult BeginReadData(UserPointer<const void*> buffer,
                            UserPointer<uint32_t> buffer_num_bytes,
@@ skipping 108 matching lines @@
   virtual MojoResult WriteMessageImplNoLock(
       UserPointer<const void> bytes,
       uint32_t num_bytes,
       std::vector<DispatcherTransport>* transports,
       MojoWriteMessageFlags flags);
   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,
+  virtual MojoResult WriteDataImplNoLock(UserPointer<const void> elements,
+                                         UserPointer<uint32_t> num_bytes,
                                          MojoWriteDataFlags flags);
   virtual MojoResult BeginWriteDataImplNoLock(
       UserPointer<void*> buffer,
       UserPointer<uint32_t> buffer_num_bytes,
       MojoWriteDataFlags flags);
   virtual MojoResult EndWriteDataImplNoLock(uint32_t num_bytes_written);
   virtual MojoResult ReadDataImplNoLock(UserPointer<void> elements,
                                         UserPointer<uint32_t> num_bytes,
                                         MojoReadDataFlags flags);
   virtual MojoResult BeginReadDataImplNoLock(
@@ skipping 136 matching lines @@
 
   Dispatcher* dispatcher_;
 
   // Copy and assign allowed.
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_SYSTEM_DISPATCHER_H_