Add the capability to include an arbitrary data stream within minidumps

src/client/windows/crash_generation/crash_generation_server.cc

Index: src/client/windows/crash_generation/crash_generation_server.cc
===================================================================
--- src/client/windows/crash_generation/crash_generation_server.cc	(revision 974)
+++ src/client/windows/crash_generation/crash_generation_server.cc	(working copy)
@@ -796,6 +796,7 @@
   assert(context);
   ClientInfo* client_info = reinterpret_cast<ClientInfo*>(context);
   client_info->PopulateCustomInfo();
+  client_info->PopulateCustomDataStream();
 
   CrashGenerationServer* crash_server = client_info->crash_server();
   assert(crash_server);
@@ -892,6 +893,7 @@
                                         GetCurrentThreadId(),
                                         client_ex_info,
                                         client.assert_info(),
+                                        client.custom_data_stream(),
                                         client.dump_type(),
                                         true,
                                         dump_path);