Fix clang-format canned check warning text

input_api.basename is a function, so printing it out yields:
"The <function basename at 0x7fccd3735410> directory requires..>"

Instead, use it to resolve the local presubmit path that has
requested clang formatting.

R=dpranke@chromium.org
BUG=422332

Review URL: https://codereview.chromium.org/665493002

git-svn-id: http://src.chromium.org/chrome/trunk/tools/depot_tools@292491 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Fix reitveld base URL for googlesource.com repos.

The base url was previously being generated as
URL@BRANCH.  I'm not sure if this works anywhere
but it certainly doesn't on googlesource.com.
Here we want URL/+/BRANCH.

R=iannucci@chromium.org, sergeyberezin@chromium.org

Review URL: https://codereview.chromium.org/652193004

git-svn-id: http://src.chromium.org/chrome/trunk/tools/depot_tools@292493 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Revert 292493 since it broke CQ

git-svn-id: http://src.chromium.org/chrome/trunk/tools/depot_tools@292513 4ff67af0-8c30-449e-8e8b-ad334ec8d88c