Upgrade Microsoft's __int8, __int16, __int32 and __int64 types from builtin defines to real types.

Otherwise statements like:
  __int64 var = __int64(0);

would be expanded to:
  long long var = long long(0);

and fail to compile.

llvm-svn: 130369
diff --git a/clang/lib/Parse/ParseExpr.cpp b/clang/lib/Parse/ParseExpr.cpp
index 8b9e5e7..91fe1e1 100644
--- a/clang/lib/Parse/ParseExpr.cpp
+++ b/clang/lib/Parse/ParseExpr.cpp
@@ -903,6 +903,7 @@
   case tok::kw_short:
   case tok::kw_int:
   case tok::kw_long:
+  case tok::kw___int64:
   case tok::kw_signed:
   case tok::kw_unsigned:
   case tok::kw_float: