`FILECHECK_OPTS` into environment for FileCheck tests.
Summary:
This fixes the following FileCheck tests:
* FileCheck/dump-input-enable.txt
* FileCheck/match-full-lines.txt
when `FILECHECK_DUMP_INPUT_ON_FAILURE` is set in the environment.
By default llvm-lit propagates `FILECHECK_DUMP_INPUT_ON_FAILURE` and
`FILECHECK_OPTS` from llvm-lit's environment into the test environment.
Unfortunately this can break FileCheck's tests because they expect that
these environment variables not to be set.
rdar://problem/47176262
Reviewers: jdenny, probinson, george.karpenkov
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D56541
llvm-svn: 350850
4d8c8fe62e