Drive-by-fix:
 - improve log parsing by not wrapping single lines in arrays

Change-Id: Ic4c5fdeb7875c8c5db57843f583e93285026ff74
BUG: chromium:757467, chromium:850038
Reviewed-on: https://chromium-review.googlesource.com/1078753
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53547}