win: allow WER to handle exceptions (#31)

In order to properly generate minidumps during actual events, it is
necessary to disable the call to `SetErrorMode()` during libuv
initialization and to remove the job flag
`JOB_OBJECT_LIMIT_DIE_ON_UNHANDLED_EXCEPTION`, both of which interfered
in the normal handling of exceptions. Finally, it was determined
prudent to include `CREATE_DEFAULT_ERROR_MODE` when spawning new
processes, to ensure that whatever error handling mode was set in the
current process is not inherited by subprocesses.

This aligns better with coredump handling on unix, where it is the
responsibility of the embedding application or user to specify the
desired behavior here.

Author: staticfloat

src/win/core.c

@@ -69,10 +69,6 @@ void uv__wake_all_loops() {
 }
 
 static void uv__init(void) {
-  /* Tell Windows that we will handle critical errors. */
-  SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX |
-               SEM_NOOPENFILEERRORBOX);
-
   /* Initialize tracking of all uv loops */
   uv__loops_init();
 

src/win/process.c

@@ -85,7 +85,6 @@ static void uv__init_global_job_handle(void) {
   info.BasicLimitInformation.LimitFlags =
       JOB_OBJECT_LIMIT_BREAKAWAY_OK |
       JOB_OBJECT_LIMIT_SILENT_BREAKAWAY_OK |
-      JOB_OBJECT_LIMIT_DIE_ON_UNHANDLED_EXCEPTION |
       JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE;
 
   uv_global_job_handle_ = CreateJobObjectW(&attr, NULL);
@@ -1073,7 +1072,7 @@ int uv_spawn(uv_loop_t* loop,
   startup.hStdOutput = uv__stdio_handle(process->child_stdio_buffer, 1);
   startup.hStdError = uv__stdio_handle(process->child_stdio_buffer, 2);
 
-  process_flags = CREATE_UNICODE_ENVIRONMENT;
+  process_flags = CREATE_UNICODE_ENVIRONMENT | CREATE_DEFAULT_ERROR_MODE;
 
   if ((options->flags & UV_PROCESS_WINDOWS_HIDE_CONSOLE) ||
       (options->flags & UV_PROCESS_WINDOWS_HIDE)) {