IDL parser: Use abspath to find test files

Before this CL, developers need to change their directory to src/tools/idl_parser
to run But it is not useful, and it is difficult to find
parse errors.
After this CL, they can find parse errors from any directories.

Bug: 650150
Change-Id: Id00649b2c594ad211d7b6e4cd45a9442cda12317
Reviewed-by: Kenichi Ishibashi <>
Commit-Queue: Hitoshi Yoshida <>
Cr-Original-Commit-Position: refs/heads/master@{#504902}
Cr-Mirrored-Commit: 70e38ec3001437528a4bf79a37ebdd9654ce9cb0
1 file changed