Merging r232675:

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r232675 | rtrieu | 2015-03-18 17:52:47 -0400 (Wed, 18 Mar 2015) | 9 lines

When cloning LocalInstantiationScope's, don't update the current scope in Sema.

Construction of LocalInstantiationScope automatically updates the current scope
inside Sema.  However, when cloning a scope, the current scope does not change.
Change the cloning function to preserve the current scope.

Review: http://reviews.llvm.org/D8407
BUG: https://llvm.org/bugs/show_bug.cgi?id=22931

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llvm-svn: 236441