Add FileReaderInterface::ReadExactly() and FileSeekerInterface::SeekSet()

util/util.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,
@@ skipping 14 matching lines @@
         '..',
         '<(INTERMEDIATE_DIR)',
       ],
       'sources': [
         'file/file_io.cc',
         'file/file_io.h',
         'file/file_io_posix.cc',
         'file/file_io_win.cc',
         'file/file_reader.cc',
         'file/file_reader.h',
+        'file/file_seeker.cc',
         'file/file_seeker.h',
         'file/file_writer.cc',
         'file/file_writer.h',
         'file/string_file.cc',
         'file/string_file.h',
         'mac/checked_mach_address_range.cc',
         'mac/checked_mach_address_range.h',
         'mac/launchd.h',
         'mac/launchd.mm',
         'mac/mac_util.cc',
@@ skipping 273 matching lines @@
     },
     {
       'target_name': 'util_test_multiprocess_exec_test_child',
       'type': 'executable',
       'sources': [
         'test/multiprocess_exec_test_child.cc',
       ],
     },
   ],
 }