trybot_patch_pool: fix logic error in previous commit
trybot_patch_pool: fix logic error in previous commit

The refactoring pushed down the patch.project, but higher callers kept
expanding it leading the code to use patch.project.project which fails.

BUG=chromium:374792
TEST=`./buildbot/run_tests` passes

Change-Id: Ia96c72e1e6c14f0b2aa7e91e98b54b36a5bc0d98
Reviewed-on: https://chromium-review.googlesource.com/200381
Reviewed-by: Yu-Ju Hong <52dc720c411f8e2156e608c1a8b894a917489667@chromium.org>
Tested-by: Mike Frysinger <8f3f75c74bd5184edcfa6534cab3c13a00a2f794@chromium.org>

chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,bpsinc-native/src_third_party_chromite