Fix issue 1968, replace usage of inline 'asm' constructs in 'stack alignment', 'jump to exception h…

vm/os_win.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/os.h"
 
 #include <time.h>
 
 #include "platform/assert.h"
 
@@ skipping 112 matching lines @@
   GetSystemInfo(&info);
   return info.dwNumberOfProcessors;
 }
 
 
 void OS::Sleep(int64_t millis) {
   ::Sleep(millis);
 }
 
 
-void OS::DebugBreak() {
-  __asm { int 3 }
-}
-
-
 void OS::Print(const char* format, ...) {
   va_list args;
   va_start(args, format);
   VFPrint(stdout, format, args);
   va_end(args);
 }
 
 
 void OS::VFPrint(FILE* stream, const char* format, va_list args) {
   vfprintf(stream, format, args);
@@ skipping 63 matching lines @@
 void OS::Abort() {
   abort();
 }
 
 
 void OS::Exit(int code) {
   exit(code);
 }
 
 }  // namespace dart