Recipes: make cwd default to slave_build

scripts/slave/recipes/ios/unified_builder_tester.expected/no_tests.json

 [
   {
     "cmd": [
       "[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 19 matching lines @@
       "--root",
       "src",
       "--revision_mapping_file",
       "{\"src\": \"got_revision\", \"src/native_client\": \"got_nacl_revision\", \"src/third_party/WebKit\": \"got_webkit_revision\", \"src/third_party/webrtc\": \"got_webrtc_revision\", \"src/tools/swarming_client\": \"got_swarming_client_revision\", \"src/v8\": \"got_v8_revision\"}",
       "--output_json",
       "/path/to/tmp/json",
       "--revision",
       "src@HEAD",
       "--force"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "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@  \"patch_failure\": false, @@@",
       "@@@STEP_LOG_LINE@json.output@  \"patch_root\": \"src\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"properties\": {@@@",
       "@@@STEP_LOG_LINE@json.output@    \"got_nacl_revision\": \"d998e125e8253980d76e269b7982aeeefc1b9b50\", @@@",
       "@@@STEP_LOG_LINE@json.output@    \"got_nacl_revision_cp\": \"refs/heads/master@{#274981}\", @@@",
@@ skipping 27 matching lines @@
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
       "[SLAVE_BUILD]/src/ios/build/bots/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@  }, @@@",
       "@@@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@  \"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  }, \n  \"compiler\": \"ninja\", \n  \"configuration\": \"Release\", \n  \"sdk\": \"iphoneos8.0\", \n  \"tests\": [], \n  \"triggered bots\": {}, \n  \"xcode version\": \"fake xcode version\"\n}"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "finalize build config"
   },
   {
     "cmd": [
       "[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",
       "[DEPOT_TOOLS]/gclient.py",
       "runhooks"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "env": {
       "GYP_CROSSCOMPILE": "1",
       "GYP_DEFINES": "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"
     },
     "name": "gclient runhooks",
     "~followup_annotations": [
       "@@@STEP_TEXT@<br />GYP_DEFINES:<br />fake gyp define 1=fake value 1<br />fake gyp define 2=fake value 2<br />component=static_library<br />OS=ios@@@"
     ]
   },
   {
     "cmd": [
       "ninja",
       "-C",
       "[SLAVE_BUILD]/src/out/Release-iphoneos"
     ],
     "cwd": "[SLAVE_BUILD]/src/out/Release-iphoneos",
     "name": "compile"
   }
 ]