Fix for header-only compile actions by Bazel#219

mikael-s-persson wants to merge 2 commits intohedronvision:mainhedronvision/bazel-compile-commands-extractor:mainfrom

mikael-s-persson:fix/syntax_only_hdr_processingmikael-s-persson/bazel-compile-commands-extractor:fix/syntax_only_hdr_processingCopy head branch name to clipboard