Merging r269882:

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r269882 | slthakur | 2016-05-18 11:39:26 +0530 (Wed, 18 May 2016) | 7 lines

[LSAN] Fix test swapcontext.cc on MIPS

There is no frame validity check in the slow unwinder like there is in the fast unwinder due to which lsan reports a leak even for heap allocated coroutine in the test swapcontext.cc. Since mips/linux uses slow unwindwer instead of fast unwinder, the test fails for mips/linux. Therefore adding the checks before unwinding fixes the test for mips/linux.

Reviewed by aizatsky.
Differential: http://reviews.llvm.org/D19961

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llvm-svn: 270672