Sync pki to chromium 5934e28579cddeae3d9ae5b5974f8aae31f200dd

This brings in pem_unittest.cc which belongs in here now with
the pem stuff.

Change-Id: I04bb16692d31e2aa9de2c146785684c05543b1a7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/63645
Commit-Queue: Bob Beck <bbe@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Auto-Submit: Bob Beck <bbe@google.com>
diff --git a/pki/fillins/path_service.h b/pki/fillins/path_service.h
index c004f9c..ccc5014 100644
--- a/pki/fillins/path_service.h
+++ b/pki/fillins/path_service.h
@@ -27,7 +27,7 @@
 };
 
 enum PathKey {
-  DIR_SOURCE_ROOT = 0,
+  BSSL_TEST_DATA_ROOT = 0,
 };
 
 class PathService {