[debuginfo-tests] Add support for moving debuginfo-tests from clang/test to llvm/projects or monorepo.

Summary:
The new version of debuginfo-tests will have it's own
lit.cfg.py file which is incompatible with the one in clang/test.
This change supports both the old and new versions, and can be used
until the bots actually move debuginfo-tests to either clang/test or
the monorepo.

This is a prerequisite for D40971.

Reviewers: zturner, aprantl

Subscribers: mgorny, JDevlieghere, llvm-commits, cfe-commits

Differential Revision: https://reviews.llvm.org/D41055

llvm-svn: 320494
diff --git a/clang/test/lit.cfg.py b/clang/test/lit.cfg.py
index 39bdf36a..8467eaa 100644
--- a/clang/test/lit.cfg.py
+++ b/clang/test/lit.cfg.py
@@ -58,12 +58,20 @@
 
 tools = [
     'c-index-test', 'clang-check', 'clang-diff', 'clang-format', 'opt',
-    ToolSubst('%test_debuginfo', command=os.path.join(
-        config.llvm_src_root, 'utils', 'test_debuginfo.pl')),
     ToolSubst('%clang_func_map', command=FindTool(
         'clang-func-mapping'), unresolved='ignore'),
 ]
 
+# FIXME: This logic can be removed once all buildbots have moved
+# debuginfo-test from clang/test to llvm/projects or monorepo.
+if os.path.exists(os.path.join(config.test_source_root, 'debuginfo-tests')):
+  if os.path.isfile(
+      os.path.join(config.test_source_root, 'debuginfo-tests', 'lit.cfg.py')):
+    config.excludes.append('debuginfo-tests')
+  else:
+    tools.append(ToolSubst('%test_debuginfo', command=os.path.join(
+      config.llvm_src_root, 'utils', 'test_debuginfo.pl')))
+
 if config.clang_examples:
     tools.append('clang-interpreter')