Merging r323998:

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r323998 | rsmith | 2018-02-01 21:01:49 +0100 (Thu, 01 Feb 2018) | 5 lines

PR36157: When injecting an implicit function declaration in C89, find the right
DeclContext rather than injecting it wherever we happen to be.

This avoids creating functions whose DeclContext is a struct or similar.

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git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_60@325104 91177308-0d34-0410-b5e6-96231b3b80d8