Roll recipe dependencies (nontrivial).

scripts/slave/recipes/webrtc/ios.expected/trybot.json

 [
   {
     "cmd": [
       "RECIPE_PACKAGE_REPO[build]/scripts/slave/ios/host_info.py",
       "--json-file",
       "/path/to/tmp/json"
     ],
-    "cwd": "[SLAVE_BUILD]",
     "name": "host and tools info",
     "~followup_annotations": [
       "@@@STEP_TEXT@<br />OS X 1.2.3, Xcode 6.7.8 (5D342509a)@@@",
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"Mac OS X Version\": \"1.2.3\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"Xcode Build Version\": \"5D342509a\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"Xcode SDKs\": [@@@",
       "@@@STEP_LOG_LINE@json.output@    \"fake sdk 1.0\", @@@",
       "@@@STEP_LOG_LINE@json.output@    \"fake sdk 1.1\", @@@",
       "@@@STEP_LOG_LINE@json.output@    \"fake sdk 2.0\"@@@",
@@ skipping 21 matching lines @@
       "--revision_mapping_file",
       "{\"src\": \"got_revision\"}",
       "--git-cache-dir",
       "[GIT_CACHE]",
       "--output_json",
       "/path/to/tmp/json",
       "--revision",
       "src@HEAD",
       "--output_manifest"
     ],
-    "cwd": "[SLAVE_BUILD]",
     "env": {
       "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]"
     },
     "name": "bot_update",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"did_run\": false, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"patch_failure\": false@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
       "[SLAVE_BUILD]/src/webrtc/build/ios/chromium.fake/ios.json",
       "/path/to/tmp/json"
     ],
-    "cwd": "[SLAVE_BUILD]",
     "name": "read build config",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"GYP_DEFINES\": {@@@",
       "@@@STEP_LOG_LINE@json.output@    \"fake gyp define 1\": \"fake value 1\", @@@",
       "@@@STEP_LOG_LINE@json.output@    \"fake gyp define 2\": \"fake value 2\", @@@",
       "@@@STEP_LOG_LINE@json.output@    \"use_goma\": \"1\"@@@",
       "@@@STEP_LOG_LINE@json.output@  }, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"compiler\": \"ninja\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"configuration\": \"Release\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"sdk\": \"iphoneos8.0\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"tests\": [], @@@",
       "@@@STEP_LOG_LINE@json.output@  \"use_analyze\": \"false\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"xcode version\": \"fake xcode version\"@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
   },
   {
     "cmd": [
       "echo",
       "-e",
       "{\n  \"GYP_DEFINES\": {\n    \"OS\": \"ios\", \n    \"component\": \"static_library\", \n    \"fake gyp define 1\": \"fake value 1\", \n    \"fake gyp define 2\": \"fake value 2\", \n    \"use_goma\": \"1\"\n  }, \n  \"additional_compile_targets\": [\n    \"All\"\n  ], \n  \"compiler\": \"ninja\", \n  \"configuration\": \"Release\", \n  \"env\": {}, \n  \"gn_args\": [], \n  \"mb_type\": null, \n  \"sdk\": \"iphoneos8.0\", \n  \"tests\": [], \n  \"triggered bots\": {}, \n  \"use_analyze\": \"false\", \n  \"xcode version\": \"fake xcode version\"\n}"
     ],
-    "cwd": "[SLAVE_BUILD]",
     "name": "finalize build config"
   },
   {
     "cmd": [
       "RECIPE_PACKAGE_REPO[build]/scripts/slave/ios/find_xcode.py",
       "--json-file",
       "/path/to/tmp/json",
       "--version",
       "fake xcode version"
     ],
-    "cwd": "[SLAVE_BUILD]",
     "name": "find xcode",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[depot_tools]/gclient.py",
       "runhooks"
     ],
-    "cwd": "[SLAVE_BUILD]",
     "env": {
       "GYP_CROSSCOMPILE": "1",
       "GYP_DEFINES": "use_goma=1 fake gyp define 1=fake value 1 fake gyp define 2=fake value 2 component=static_library OS=ios",
       "GYP_GENERATORS": "ninja",
       "LANDMINES_VERBOSE": "1",
       "PATH": "%(PATH)s:RECIPE_PACKAGE_REPO[depot_tools]"
     },
     "name": "gclient runhooks",
     "~followup_annotations": [
       "@@@STEP_TEXT@<br />GYP_DEFINES:<br />use_goma=1<br />fake gyp define 1=fake value 1<br />fake gyp define 2=fake value 2<br />component=static_library<br />OS=ios@@@"
     ]
   },
   {
     "allow_subannotations": true,
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE_REPO[build]/scripts/slave/clang_revision.py",
       "--src-dir",
       "[SLAVE_BUILD]/src",
       "--output-json",
       "/path/to/tmp/json"
     ],
-    "cwd": "[SLAVE_BUILD]",
     "env": {
       "GOMA_SERVICE_ACCOUNT_JSON_FILE": "/creds/service_accounts/service-account-goma-client.json"
     },
     "name": "clang_revision",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"clang_revision\": \"123456-7\"@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
@@ skipping 38 matching lines @@
       "@@@STEP_LOG_LINE@json.output (invalid)@null@@@",
       "@@@STEP_LOG_END@json.output (invalid)@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]