Merging r338553:

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r338553 | filcab | 2018-08-01 15:41:42 +0200 (Wed, 01 Aug 2018) | 1 line

Use a dummy target so the test passes when default target is for a toolchain implements useIntegratedAs() -> true
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git-svn-id: https://llvm.org/svn/llvm-project/cfe/branches/release_70@338688 91177308-0d34-0410-b5e6-96231b3b80d8