Merging r311835:

Merging r311835:
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r311835 | dhinton | 2017-08-26 14:08:51 -0700 (Sat, 26 Aug 2017) | 12 lines

[Dominators] Remove redundant explicit template instantiation.

Summary:
Remove redundant explicit template instantiation.

This was reported by Andrew Kelley building release_50 with gcc7.2.0 on MacOS: duplicate symbol llvm::DominatorTreeBase.

Reviewers: kuhar, andrewrk, davide, hans

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D37185
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_50@312014 91177308-0d34-0410-b5e6-96231b3b80d8