Bug 1360609 - Only run toolchain jobs on trunk and try. r=dustin

Until bug 1313111, no job depends on them, so it's still necessary to
run them on trunk and try, but we want to avoid running them on release
branches on every push.

After bug 1313111, we'll be able to empty the `run-on-projects` list and
let them be pulled as dependencies of other jobs.

--HG--
extra : rebase_source : 20144418da6a97cd76ac09a569903641932fa7a1

taskcluster/taskgraph/transforms/job/toolchain.py

@@ -71,6 +71,8 @@ def add_optimizations(config, run, taskdesc):
 @run_job_using("docker-worker", "toolchain-script", schema=toolchain_run_schema)
 def docker_worker_toolchain(config, job, taskdesc):
     run = job['run']
+    taskdesc['run-on-projects'] = ['autoland', 'mozilla-inbound',
+                                   'mozilla-central', 'try']
 
     worker = taskdesc['worker']
     worker['artifacts'] = []
@@ -135,6 +137,8 @@ def docker_worker_toolchain(config, job, taskdesc):
 @run_job_using("generic-worker", "toolchain-script", schema=toolchain_run_schema)
 def windows_toolchain(config, job, taskdesc):
     run = job['run']
+    taskdesc['run-on-projects'] = ['autoland', 'mozilla-inbound',
+                                   'mozilla-central', 'try']
 
     worker = taskdesc['worker']