Extract MethodNotAllowed as an API exception

This allows views to throw with a proper HTTP error code if
a specific method is not a valid call on a resource.

Change-Id: Iad15024edd66ab3908c5b4e7319b8956b935b8a2

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/restapi/MethodNotAllowedException.java

@@ -0,0 +1,20 @@
+// Copyright (C) 2012 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.restapi;
+
+/** Method is not acceptable on the resource (HTTP 405 Method Not Allowed). */
+public class MethodNotAllowedException extends RestApiException {
+  private static final long serialVersionUID = 1L;
+}