Mojo: Add a Mojo-specific multiprocess test base class.

mojo/system/platform_channel.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_PLATFORM_CHANNEL_H_
 #define MOJO_SYSTEM_PLATFORM_CHANNEL_H_
 
 #include <string>
 #include <utility>
 
@@ skipping 29 matching lines @@
 };
 
 class PlatformClientChannel;
 
 // A server channel has an "implicit" client channel created with it. This may
 // be a real channel (in the case of POSIX, in which case there's an actual FD
 // for it) or fake.
 //  - That client channel may then be used in-process (e.g., for single process
 //    tests) by getting a |PlatformClientChannel| using |CreateClientChannel()|.
 //  - Or it may be "passed" to a new child process using
-//    |PrepareToPassClientChannelToChildProcess()|, etc. (see below). The child
-//    process would then get a |PlatformClientChannel| by using
+//    |GetDataNeededToPassClientChannelToChildProcess()|, etc. (see below). The
+//    child process would then get a |PlatformClientChannel| by using
 //    |PlatformClientChannel::CreateFromParentProcess()|.
 //  - In both these cases, "ownership" of the client channel is transferred (to
 //    the |PlatformClientChannel| or the child process).
 // TODO(vtl): Add ways of passing it to other existing processes.
 class MOJO_SYSTEM_EXPORT PlatformServerChannel : public PlatformChannel {
  public:
   virtual ~PlatformServerChannel() {}
 
   static scoped_ptr<PlatformServerChannel> Create(const std::string& name);
 
   // For in-process use, from a server channel you can make a corresponding
   // client channel.
   virtual scoped_ptr<PlatformClientChannel> CreateClientChannel() = 0;
 
   // Prepares to pass the client channel to a new child process, to be launched
   // using |LaunchProcess()| (from base/launch.h). Modifies |*command_line| and
   // |*file_handle_mapping| as needed. (|file_handle_mapping| may be null on
   // platforms that don't need it, like Windows.)
-  virtual void PrepareToPassClientChannelToChildProcess(
+  virtual void GetDataNeededToPassClientChannelToChildProcess(
       CommandLine* command_line,
-      base::FileHandleMappingVector* file_handle_mapping) = 0;
+      base::FileHandleMappingVector* file_handle_mapping) const = 0;
   // To be called once the child process has been successfully launched, to do
   // any cleanup necessary.
   virtual void ChildProcessLaunched() = 0;
 
   const std::string& name() const { return name_; }
 
  protected:
   explicit PlatformServerChannel(const std::string& name);
 
  private:
   const std::string name_;
 
   DISALLOW_COPY_AND_ASSIGN(PlatformServerChannel);
 };
 
 class MOJO_SYSTEM_EXPORT PlatformClientChannel : public PlatformChannel {
  public:
   virtual ~PlatformClientChannel() {}
 
   // Creates a client channel if you already have the underlying handle for it.
   // Note: This takes ownership of |handle|.
   static scoped_ptr<PlatformClientChannel> CreateFromHandle(
       const PlatformChannelHandle& handle);
 
   // To be called to get a client channel passed from the parent process, using
-  // |PlatformServerChannel::PrepareToPassClientChannelToChildProcess()|, etc.
-  // Returns null on failure.
+  // |PlatformServerChannel::GetDataNeededToPassClientChannelToChildProcess()|,
+  // etc. Returns null on failure.
   static scoped_ptr<PlatformClientChannel> CreateFromParentProcess(
       const CommandLine& command_line);
 
  private:
   PlatformClientChannel() {}
 
   DISALLOW_COPY_AND_ASSIGN(PlatformClientChannel);
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_SYSTEM_PLATFORM_CHANNEL_H_