Roll recipe dependencies (nontrivial).

scripts/slave/recipes/nacl.expected/linux_triggering.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_MODULE[depot_tools::bot_update]/resources/bot_update.py",
       "--spec",
       "cache_dir = '[GIT_CACHE]'\nsolutions = [{'deps_file': '.DEPS.git', 'managed': True, 'name': 'native_client', 'url': 'https://chromium.googlesource.com/native_client/src/native_client.git'}]",
       "--patch_root",
       "native_client",
@@ skipping 63 matching lines @@
       "BUILDBOT_BUILDERNAME": "precise_64-newlib-arm_qemu-pnacl-dbg",
       "BUILDBOT_GOT_REVISION": "a95eb4c044a154d692a53fdfa564ee8de7aeea5b",
       "BUILDBOT_MASTERNAME": "client.nacl",
       "BUILDBOT_REVISION": "abcd",
       "BUILDBOT_SLAVE_TYPE": "BuilderTester",
       "RUNTEST": "[BUILD]/scripts/slave/runtest.py"
     },
     "name": "annotated steps"
   },
   {
-    "cmd": [],
     "name": "trigger",
     "trigger_specs": [
       {
         "builder_name": "oneiric_32-newlib-arm_hw-pnacl-panda-dbg",
         "properties": {
           "parent_slavename": "TestSlave"
         }
       }
     ],
     "~followup_annotations": [
       "@@@STEP_TEXT@oneiric_32-newlib-arm_hw-pnacl-panda-dbg@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]