Add global presubmit that JSON and IDL files can be parsed.

chrome/common/extensions/api/test_presubmit/valid_idl_basics.idl

-// 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.
-
-// Tests a valid IDL file.
-
-namespace idl_basics {
-  enum EnumType {
-    name1,
-    name2
-  };
-
-  dictionary MyType1 {
-    DOMString a;
-  };
-
-  callback Callback1 = void();
-  callback Callback2 = void(long x);
-  callback Callback3 = void(MyType1 arg);
-  callback Callback4 = void(EnumType type);
-
-  interface Functions {
-    static void function1();
-    static void function2(long x);
-    static void function3(MyType1 arg);
-    static void function4(Callback1 cb);
-    static void function5(Callback2 cb);
-    static void function6(Callback3 cb);
-    static void function7(Callback4 cb);
-  };
-
-  interface Events {
-    static void onFoo1();
-    static void onFoo2(long x);
-    static void onFoo2(MyType1 arg);
-    static void onFoo3(EnumType type);
-  };
-};