env/commit-watcher: bump version

Change-Id: I8a40ad5b2630591923897487bb147142821437ec
Reviewed-on: https://go-review.googlesource.com/11116
Reviewed-by: Andrew Gerrand <adg@golang.org>

env/commit-watcher/Dockerfile

@@ -14,4 +14,4 @@ RUN /scripts/install-apt-deps.sh
 
 ADD /scripts/build-commit-watcher.sh /scripts/
 # Note that WATCHER_REV must be full for "git fetch origin $REV" later:
-RUN GO_REV=go1.4 TOOLS_REV=a54d0066172 WATCHER_REV=89ace0b562ee0e4424941a285df09002d72a6a9a /scripts/build-commit-watcher.sh && test -f /usr/local/bin/watcher
+RUN GO_REV=go1.4 TOOLS_REV=a54d0066172 WATCHER_REV=1b1e086fd18435e4ea46287fed6c85f268f47bf7 /scripts/build-commit-watcher.sh && test -f /usr/local/bin/watcher