Merging r258609:

Merging r258609:
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r258609 | majnemer | 2016-01-22 21:41:22 -0800 (Fri, 22 Jan 2016) | 5 lines

[PruneEH] Reuse code from removeUnwindEdge

PruneEH had functionality idential to removeUnwindEdge.
Consolidate around removeUnwindEdge.
No functionality change is intended.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_38@261129 91177308-0d34-0410-b5e6-96231b3b80d8