Merging r351577:

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r351577 | ssijaric | 2019-01-18 11:34:20 -0800 (Fri, 18 Jan 2019) | 5 lines

Fix the buildbot issue introduced by r351421

The EXPENSIVE_CHECK x86_64 Windows buildbot is failing due to this change. Fix
the map access.

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llvm-svn: 363006