Create ExtensionsRendererClient.

apps/shell/renderer/shell_extensions_renderer_client.cc

Index: apps/shell/renderer/shell_extensions_renderer_client.cc
diff --git a/apps/shell/renderer/shell_extensions_renderer_client.cc b/apps/shell/renderer/shell_extensions_renderer_client.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c5de265ea13273021d3898f8aea4d37b0c17dea7
--- /dev/null
+++ b/apps/shell/renderer/shell_extensions_renderer_client.cc
@@ -0,0 +1,25 @@
+// 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 "apps/shell/renderer/shell_extensions_renderer_client.h"
+
+namespace apps {
+
+ShellExtensionsRendererClient::ShellExtensionsRendererClient() {}
+
+ShellExtensionsRendererClient::~ShellExtensionsRendererClient() {}
+
+bool ShellExtensionsRendererClient::IsIncognitoProcess() const {
+  // app_shell doesn't support off-the-record contexts.
+  return false;
+}
+
+int ShellExtensionsRendererClient::GetLowestIsolatedWorldId() const {
+  // app_shell doesn't need to reserve world IDs for anything other than
+  // extensions, so we always return 1. Note that 0 is reserved for the global
+  // world.
+  return 1;
+}
+
+}  // namespace apps