Merging r268531:

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r268531 | koriakin | 2016-05-04 19:39:14 +0100 (Wed, 04 May 2016) | 3 lines

[MSan] [Mips64] Add tests for vararg handling.

Differential Revision: http://reviews.llvm.org/D19919
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llvm-svn: 271120