Remove SimpleBroker and instead use the production broker implementation in tests.

mojo/runner/host/child_process.cc

 // Copyright 2014 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/runner/host/child_process.h"
 
 #include "base/base_switches.h"
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/command_line.h"
@@ skipping 343 matching lines @@
 
 #if defined(OS_LINUX) && !defined(OS_ANDROID)
   scoped_ptr<mojo::runner::LinuxSandbox> sandbox;
 #endif
   base::NativeLibrary app_library = 0;
   // Load the application library before we engage the sandbox.
   app_library = mojo::runner::LoadNativeApplication(
       command_line.GetSwitchValuePath(switches::kChildProcess));
 
   base::i18n::InitializeICU();
-  CallLibraryEarlyInitialization(app_library);
+  if (app_library)
+    CallLibraryEarlyInitialization(app_library);
 #if defined(OS_LINUX) && !defined(OS_ANDROID)
   if (command_line.HasSwitch(switches::kEnableSandbox))
     sandbox = InitializeSandbox();
 #endif
 
   embedder::ScopedPlatformHandle platform_channel =
       embedder::PlatformChannelPair::PassClientHandleFromParentProcess(
           command_line);
   CHECK(platform_channel.is_valid());
 
@@ skipping 12 matching lines @@
   // This will block, then run whatever the controller wants.
   blocker.Block();
 
   app_context.Shutdown();
 
   return 0;
 }
 
 }  // namespace runner
 }  // namespace mojo