Mojo: (POSIX) Pass channel handle to child.

mojo/common/test/multiprocess_test_base.cc

 // 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.
 
 #include "mojo/common/test/multiprocess_test_base.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/process/kill.h"
 #include "base/process/process_handle.h"
+// TODO(vtl): Remove build_config.h include when fully implemented on Windows.
 #include "build/build_config.h"
 
 namespace mojo {
 namespace test {
 
 MultiprocessTestBase::MultiprocessTestBase()
     : test_child_handle_(base::kNullProcessHandle) {
 }
 
 MultiprocessTestBase::~MultiprocessTestBase() {
@@ skipping 68 matching lines @@
 #if defined(OS_POSIX)
   base::FileHandleMappingVector unused;
   platform_server_channel_->GetDataNeededToPassClientChannelToChildProcess(
       &command_line, &unused);
 #endif
   return command_line;
 }
 
 // static
 void MultiprocessTestBase::ChildSetup() {
-  // TODO(vtl)
-  NOTIMPLEMENTED();
+  CHECK(CommandLine::InitializedForCurrentProcess());
+// TODO(vtl): Not implemented on Windows yet.
+#if defined(OS_POSIX)
+  platform_client_channel =
+      system::PlatformClientChannel::CreateFromParentProcess(
+          *CommandLine::ForCurrentProcess());
+  CHECK(platform_client_channel.get());
+#endif
 }
 
+// static
+scoped_ptr<system::PlatformClientChannel>
+    MultiprocessTestBase::platform_client_channel;
+
 }  // namespace test
 }  // namespace mojo