win: Add and use a custom CaptureContext() implementation

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 131 matching lines @@
         'synchronization/semaphore_posix.cc',
         'synchronization/semaphore_win.cc',
         'synchronization/semaphore.h',
         'thread/thread.cc',
         'thread/thread.h',
         'thread/thread_log_messages.cc',
         'thread/thread_log_messages.h',
         'thread/thread_posix.cc',
         'thread/thread_win.cc',
         'win/address_types.h',
+        'win/capture_context.asm',
+        'win/capture_context.h',
         'win/checked_win_address_range.h',
         'win/exception_handler_server.cc',
         'win/exception_handler_server.h',
         'win/module_version.cc',
         'win/module_version.h',
         'win/nt_internals.cc',
         'win/nt_internals.h',
         'win/ntstatus_logging.cc',
         'win/ntstatus_logging.h',
         'win/process_info.cc',
@@ skipping 71 matching lines @@
             ],
           },
         }],
         ['OS=="win"', {
           'link_settings': {
             'libraries': [
               '-lrpcrt4.lib',
               '-lwinhttp.lib',
             ],
           },
+          'conditions': [
+            ['target_arch=="ia32"', {
+              'msvs_settings': {
+                'MASM': {
+                  'UseSafeExceptionHandlers': 'true',
+                },
+              },
+            }],
+            ['target_arch=="x64"', {
+              'rules': [
+                {
+                  # .asm files aren’t assembled by the Windows toolchain by
+                  # default on x86_64.
+                  'rule_name': 'Assemble',
+                  'msvs_cygwin_shell': 0,
+                  'msvs_quote_cmd': 0,
+                  'extension': 'asm',
+                  'inputs': [],
+                  'outputs': [
+                    '<(INTERMEDIATE_DIR)/<(RULE_INPUT_ROOT).obj',
+                  ],
+                  'action': [
+                    'ml64',
+                    '/nologo',
+                    '/Fo',
+                    '<(INTERMEDIATE_DIR)\\<(RULE_INPUT_ROOT).obj',
+                    '/c',
+                    '<(RULE_INPUT_PATH)',
+                  ],
+                  'process_outputs_as_sources': 1,
+                  'message': 'Assembling <(RULE_INPUT_PATH)',
+                },
+              ],
+            }],
+          ],
         }],
       ],
     },
   ],
 }