Introduce MinidumpWritable, its dependencies, and their tests

crashpad.gyp

 # Copyright 2014 The Crashpad Authors. All rights reserved.
 #
 # 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.
 
 {
   'targets': [
     {
       'target_name': 'All',
       'type': 'none',
       'suppress_wildcard': 1,
       'dependencies': [
         'compat/compat.gyp:*',
+        'minidump/minidump.gyp:*',
+        'util/util.gyp:*',
       ],
       'sources': [
         'crashpad.doxy.h',
         'package.h',
       ],
     },
   ],
 }