Introduce apps API target in //apps and move app.runtime API into it

apps/shell/browser/shell_extensions_browser_client.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 "apps/shell/browser/shell_extensions_browser_client.h"
 
+#include "apps/common/api/generated_api.h"
 #include "apps/shell/browser/shell_app_sorting.h"
 #include "apps/shell/browser/shell_extension_system_factory.h"
 #include "apps/shell/browser/shell_extension_web_contents_observer.h"
 #include "base/prefs/pref_service.h"
 #include "base/prefs/pref_service_factory.h"
 #include "base/prefs/testing_pref_store.h"
 #include "chrome/common/extensions/api/generated_api.h"
 #include "components/user_prefs/pref_registry_syncable.h"
 #include "components/user_prefs/user_prefs.h"
 #include "extensions/browser/api/extensions_api_client.h"
@@ skipping 173 matching lines @@
   return NULL;
 }
 
 ExtensionSystemProvider*
 ShellExtensionsBrowserClient::GetExtensionSystemFactory() {
   return ShellExtensionSystemFactory::GetInstance();
 }
 
 void ShellExtensionsBrowserClient::RegisterExtensionFunctions(
     ExtensionFunctionRegistry* registry) const {
+  // Generated APIs from lower-level modules.
   extensions::core_api::GeneratedFunctionRegistry::RegisterAll(registry);
+  apps::api::GeneratedFunctionRegistry::RegisterAll(registry);
+
   // TODO(rockot): Remove dependency on src/chrome once we have some core APIs
   // moved out. See http://crbug.com/349042.
   extensions::api::GeneratedFunctionRegistry::RegisterAll(registry);
 }
 
 }  // namespace extensions