Remove host_path_finder.py.
Remove host_path_finder.py.

This module seems unused. It was initially used in one function,
PurgeUnpinnedAshmem from android_commands.py which seems to be
gone. This cleanup is part of my quest to remove code that
contains "out/Debug" or "out/Release" explicitly.

BUG=

Review URL: https://codereview.chromium.org/1310283004

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#345930}

Chilledheart/chromium,Chilledheart/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,Chilledheart/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,Chilledheart/chromium,Chilledheart/chromium,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk