Add appengine/gcloud/mustache dependencies.

pkg/appengine/lib/src/protobuf_api/rpc/rpc_service_remote_api.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+library rpc_service_remote_api;
+
+import 'dart:async';
+import 'dart:io';
+
+import 'rpc_service.dart';
+import 'rpc_service_base.dart';
+import '../internal/remote_api.pb.dart' as remote_api;
+
+
+class RPCServiceRemoteApi extends RPCServiceBase implements RPCService {
+  static const Map<String, String> ADDITIONAL_HEADERS = const <String,String> {
+      'X-Google-RPC-Service-Endpoint': 'app-engine-apis',
+      'X-Google-RPC-Service-Method': '/VMRemoteAPI.CallRemoteAPI',
+  };
+
+  final String hostname;
+  final int port;
+  final String path;
+  HttpClient _client;
+
+  RPCServiceRemoteApi(this.hostname, this.port, {this.path: '/rpc_http'}) {
+    _client = new HttpClient();
+  }
+
+  Future<List<int>> call(String apiPackage,
+                         String method,
+                         List<int> requestProtocolBuffer,
+                         {String ticket: 'invalid-ticket'}) {
+    var apiRequest = new remote_api.Request();
+    apiRequest.serviceName = apiPackage;
+    apiRequest.method = method;
+    apiRequest.request = requestProtocolBuffer;
+    apiRequest.requestId = ticket;
+    return _call(apiRequest).then((remote_api.Response apiResponse) {
+      if (apiResponse.hasApplicationError()) {
+        throw new RpcApplicationError(
+            apiResponse.applicationError.code,
+            apiResponse.applicationError.detail);
+      }
+      // This can e.g. happen if the request ticket is invalid.
+      if (apiResponse.hasRpcError()) {
+        throw new Exception('An internal error occured while making a RPC call '
+            '(${apiResponse.rpcError.toString().replaceAll('\n','  ')}).');
+      }
+      return apiResponse.response;
+    });
+  }
+
+  Future<remote_api.Response> _call(remote_api.Request rpcRequest) {
+    return makeRequest(hostname,
+                       port,
+                       path,
+                       rpcRequest.writeToBuffer(),
+                       ADDITIONAL_HEADERS).then((List<int> responseData) {
+      return new remote_api.Response.fromBuffer(responseData);
+    });
+  }
+}