Roll recipe dependencies (nontrivial).

scripts/slave/recipes/chromium_codesearch.expected/full_Chromium_Linux_Codesearch_Builder.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': 'src', 'url': 'https://chromium.googlesource.com/chromium/src.git'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'tools/chrome-devtools-frontend', 'url': 'https://chromium.googlesource.com/chromium/tools/chrome-devtools-frontend'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'tools/gsd_generate_index', 'url': 'https://chromium.googlesource.com/chromium/tools/gsd_generate_index'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'tools/perf', 'url': 'https://chromium.googlesource.com/chromium/tools/perf'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'tools/command_wrapper/bin', 'url': 'https://chromium.googlesource.com/chromium/tools/command_wrapper/bin'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'tools/depot_tools', 'url': 'https://chromium.googlesource.com/chromium/tools/depot_tools'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'tools/chromium-jobqueue', 'url': 'https://chromium.googlesource.com/chromium/tools/chromium-jobqueue'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'tools/chromium-shortener', 'url': 'https://chromium.googlesource.com/chromium/tools/chromium-shortener'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'tools/deps2git', 'url': 'https://chromium.googlesource.com/chromium/tools/deps2git'}, {'deps_file': '.DEPS.git', 'managed': True, 'name': 'infra', 'url': 'https://chromium.googlesource.com/infra/infra'}]",
       "--patch_root",
       "src",
       "--revision_mapping_file",
       "{\"src\": \"got_revision\", \"src/buildtools\": \"got_buildtools_revision\", \"src/native_client\": \"got_nacl_revision\", \"src/third_party/angle\": \"got_angle_revision\", \"src/third_party/webrtc\": \"got_webrtc_revision\", \"src/tools/swarming_client\": \"got_swarming_client_revision\", \"src/v8\": \"got_v8_revision\"}",
       "--git-cache-dir",
       "[GIT_CACHE]",
       "--output_json",
       "/path/to/tmp/json",
       "--revision",
       "src@HEAD",
       "--output_manifest"
     ],
     "env": {
-      "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]"
+      "PATH": "RECIPE_PACKAGE_REPO[depot_tools]:%(PATH)s"
     },
     "name": "bot_update",
     "~followup_annotations": [
       "@@@STEP_TEXT@Some step text@@@",
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"did_run\": true, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"fixed_revisions\": {@@@",
       "@@@STEP_LOG_LINE@json.output@    \"src\": \"HEAD\"@@@",
       "@@@STEP_LOG_LINE@json.output@  }, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"manifest\": {@@@",
@@ skipping 191 matching lines @@
       "@@@STEP_LOG_LINE@json.output (invalid)@null@@@",
       "@@@STEP_LOG_END@json.output (invalid)@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]