Recipes: make cwd default to slave_build

scripts/slave/recipes/chromium.expected/full_chromium_fyi_CrWinClang_shared_.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]\\scripts\\slave\\kill_processes.py"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "taskkill"
   },
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]\\scripts\\slave\\bot_update.py",
       "--master",
       "chromium.fyi",
       "--builder",
       "CrWinClang(shared)",
       "--slave",
       "TestSlavename",
       "--spec",
       "cache_dir = None\nsolutions = [{'custom_vars': {'googlecode_url': 'svn://svn-mirror.golo.chromium.org/%s', 'nacl_trunk': 'svn://svn-mirror.golo.chromium.org/native_client/trunk', 'sourceforge_url': 'svn://svn-mirror.golo.chromium.org/%(repo)s', 'webkit_trunk': 'svn://svn-mirror.golo.chromium.org/blink/trunk'}, 'deps_file': 'DEPS', 'managed': True, 'name': 'src', 'url': 'svn://svn-mirror.golo.chromium.org/chrome/trunk/src'}]",
       "--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"
     ],
+    "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 26 matching lines @@
       "@@@SET_BUILD_PROPERTY@got_revision_cp@\"refs/heads/master@{#170242}\"@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[SLAVE_BUILD]\\src\\tools\\swarming_client\\swarming.py",
       "--version"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "swarming.py --version",
     "stdout": "/path/to/tmp/",
     "~followup_annotations": [
       "@@@STEP_TEXT@0.4.10@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[DEPOT_TOOLS]\\gclient.py",
       "runhooks"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "env": {
       "GYP_DEFINES": "clang=1 component=shared_library fastbuild=1 target_arch=ia32 test_isolation_mode=prepare"
     },
     "name": "gclient runhooks"
   },
   {
     "cmd": [
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
       "[SLAVE_BUILD]\\src\\testing\\buildbot\\chromium.fyi.json",
       "/path/to/tmp/json"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "read test spec",
     "~followup_annotations": [
       "@@@STEP_TEXT@path: [SLAVE_BUILD]\\src\\testing\\buildbot\\chromium.fyi.json@@@",
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"CrWinClang(shared) tester\": {@@@",
       "@@@STEP_LOG_LINE@json.output@    \"gtest_tests\": [@@@",
       "@@@STEP_LOG_LINE@json.output@      {@@@",
       "@@@STEP_LOG_LINE@json.output@        \"swarming\": {@@@",
       "@@@STEP_LOG_LINE@json.output@          \"can_use_on_swarming_builders\": true@@@",
       "@@@STEP_LOG_LINE@json.output@        }, @@@",
@@ skipping 13 matching lines @@
       "--output",
       "/path/to/tmp/json",
       "--",
       "--build-config-fs",
       "Release",
       "--paths",
       "{\"build\": \"[BUILD]\", \"checkout\": \"[SLAVE_BUILD]\\\\src\"}",
       "--properties",
       "{\"buildername\": \"CrWinClang(shared)\", \"buildnumber\": 571, \"mastername\": \"chromium.fyi\", \"slavename\": \"TestSlavename\", \"target_platform\": \"win\"}"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "get compile targets for scripts",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]\\scripts\\slave\\cleanup_temp.py"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "cleanup_temp"
   },
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_MODULE[isolate]\\resources\\find_isolated_tests.py",
       "--build-dir",
       "[SLAVE_BUILD]\\src\\out\\Release",
       "--clean-isolated-files"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "clean isolated files"
   },
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]\\scripts\\slave\\compile.py",
       "--target",
       "Release",
       "--src-dir",
       "[SLAVE_BUILD]\\src",
       "--build-tool",
       "ninja",
       "--compiler",
       "clang",
       "--"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "compile"
   },
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_MODULE[isolate]\\resources\\remove_build_metadata.py",
       "--build-dir",
       "[SLAVE_BUILD]\\src\\out\\Release",
       "--src-dir",
       "[SLAVE_BUILD]\\src"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "remove_build_metadata"
   },
   {
     "cmd": [
       "python",
       "-u",
       "[SLAVE_BUILD]\\src\\tools\\swarming_client\\isolate.py",
       "batcharchive",
       "--dump-json",
       "/path/to/tmp/json",
       "--isolate-server",
       "https://isolateserver.appspot.com",
       "--verbose",
       "[SLAVE_BUILD]\\src\\out\\Release\\browser_tests.isolated.gen.json"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "isolate tests",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"browser_tests\": \"[dummy hash for browser_tests]\"@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@"
     ]
   },
   {
     "allow_subannotations": true,
     "cmd": [
       "python",
       "-u",
       "[BUILD]\\scripts\\slave\\zip_build.py",
       "--target",
       "Release",
       "--build-url",
       "gs://chromium-fyi-archive/chromium.fyi/CrWinClang(shared)",
       "--build_revision",
       "f27fede2220bcd326aee3e86ddfd4ebd0fe58cb9",
       "--factory-properties",
       "{\"blamelist\": [\"cool_dev1337@chromium.org\", \"hax@chromium.org\"], \"buildername\": \"CrWinClang(shared)\", \"buildnumber\": 571, \"mastername\": \"chromium.fyi\", \"parent_buildername\": null, \"recipe\": \"chromium\", \"slavename\": \"TestSlavename\", \"workdir\": \"/path/to/workdir/TestSlavename\"}",
       "--build-properties",
       "{\"blamelist\": [\"cool_dev1337@chromium.org\", \"hax@chromium.org\"], \"buildername\": \"CrWinClang(shared)\", \"buildnumber\": 571, \"mastername\": \"chromium.fyi\", \"parent_buildername\": null, \"recipe\": \"chromium\", \"slavename\": \"TestSlavename\", \"workdir\": \"/path/to/workdir/TestSlavename\"}"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "package build"
   }
 ]