Revert "[clangd] Migrate last tweak tests to TweakTesting.h and remove old helpers. NFC"

This reverts commit 8f85685b5cf57eddea11fa444503ade220c724e4, which
breaks on old gcc that have the macro + raw strings bug.

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@370262 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed