Introduce chrome.shell.createWindow stub API for app_shell

apps/shell/browser/shell_extensions_browser_client.cc

Index: apps/shell/browser/shell_extensions_browser_client.cc
diff --git a/apps/shell/browser/shell_extensions_browser_client.cc b/apps/shell/browser/shell_extensions_browser_client.cc
index 7dcf7417c868d954a2dd6d2581580c3805ffb638..e84bf096ebb8bfe7ed2d620c3858952d09f5a7ce 100644
--- a/apps/shell/browser/shell_extensions_browser_client.cc
+++ b/apps/shell/browser/shell_extensions_browser_client.cc
@@ -8,6 +8,7 @@
 #include "apps/shell/browser/shell_app_window_api.h"
 #include "apps/shell/browser/shell_extension_system_factory.h"
 #include "apps/shell/browser/shell_extension_web_contents_observer.h"
+#include "apps/shell/common/api/generated_api.h"
 #include "base/prefs/pref_service.h"
 #include "base/prefs/pref_service_factory.h"
 #include "base/prefs/testing_pref_store.h"
@@ -231,6 +232,9 @@ void ShellExtensionsBrowserClient::RegisterExtensionFunctions(
   // moved out. Also clean up the comment below. See http://crbug.com/349042.
   extensions::api::GeneratedFunctionRegistry::RegisterAll(registry);
 
+  // Register chrome.shell APIs.
+  apps::shell_api::GeneratedFunctionRegistry::RegisterAll(registry);
+
   // Register our simplified implementation for chrome.app.window.create().
   registry->RegisterFunction<ShellAppWindowCreateFunction>();
 }