reland of intsafe precompiled header fix from https://codereview.chromium.org/14201003/

build/intsafe_workaround.h

Index: build/intsafe_workaround.h
diff --git a/build/intsafe_workaround.h b/build/intsafe_workaround.h
new file mode 100644
index 0000000000000000000000000000000000000000..8d459cbe3658650f8d390fe4572d38c3031a8e26
--- /dev/null
+++ b/build/intsafe_workaround.h
@@ -0,0 +1,27 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BUILD_INTSAFE_WORKAROUND_H_
+#define BUILD_INTSAFE_WORKAROUND_H_
+
+// Workaround for:
+// http://connect.microsoft.com/VisualStudio/feedback/details/621653/
+// http://crbug.com/225822
+// Note that we can't actually include <stdint.h> here because there's other
+// code in third_party that has partial versions of stdint types that conflict.
+#include <intsafe.h>
+#undef INT8_MIN
+#undef INT16_MIN
+#undef INT32_MIN
+#undef INT64_MIN
+#undef INT8_MAX
+#undef UINT8_MAX
+#undef INT16_MAX
+#undef UINT16_MAX
+#undef INT32_MAX
+#undef UINT32_MAX
+#undef INT64_MAX
+#undef UINT64_MAX
+
+#endif  // BUILD_INTSAFE_WORKAROUND_H_