Recipes: make cwd default to slave_build

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

 [
   {
     "cmd": [
       "python",
       "-u",
       "[DEPOT_TOOLS]/gclient.py",
       "sync",
       "--verbose",
       "--force",
       "--revision",
@@ skipping 17 matching lines @@
       "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",
       "[DEPOT_TOOLS]/gclient.py",
       "runhooks"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "env": {
       "GYP_DEFINES": "component=static_library gomadir='[BUILD]/goma' target_arch=ia32 use_goma=1"
     },
     "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_END@json.output@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[SLAVE_BUILD]/src/testing/scripts/get_compile_targets.py",
       "--output",
       "/path/to/tmp/json",
       "--",
       "--build-config-fs",
       "Release",
       "--paths",
       "{\"build\": \"[BUILD]\", \"checkout\": \"[SLAVE_BUILD]/src\"}",
       "--properties",
       "{\"buildername\": \"CrWinGoma\", \"buildnumber\": 571, \"mastername\": \"chromium.fyi\", \"slavename\": \"TestSlavename\", \"target_platform\": \"linux\"}"
     ],
+    "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",
       "[BUILD]/scripts/slave/compile.py",
       "--target",
       "Release",
       "--src-dir",
       "[SLAVE_BUILD]/src",
       "--build-tool",
       "ninja",
       "--compiler",
       "goma",
       "--goma-dir",
       "[BUILD]/goma",
       "--goma-hermetic",
       "error",
       "--",
       "base_unittests",
       "chromium_builder_tests",
       "content_unittests"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "compile"
   },
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]/goma/diagnose_goma_log.py"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "diagnose_goma",
     "~followup_annotations": [
       "step returned non-zero exit code: 1",
       "@@@STEP_FAILURE@@@"
     ]
   },
   {
     "allow_subannotations": true,
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/runtest.py",
       "--target",
       "Release",
       "--xvfb",
       "--factory-properties",
       "{\"blamelist\": [\"cool_dev1337@chromium.org\", \"hax@chromium.org\"], \"buildername\": \"CrWinGoma\", \"buildnumber\": 571, \"mastername\": \"chromium.fyi\", \"recipe\": \"chromium\", \"slavename\": \"TestSlavename\", \"workdir\": \"/path/to/workdir/TestSlavename\"}",
       "--build-properties",
       "{\"blamelist\": [\"cool_dev1337@chromium.org\", \"hax@chromium.org\"], \"buildername\": \"CrWinGoma\", \"buildnumber\": 571, \"mastername\": \"chromium.fyi\", \"recipe\": \"chromium\", \"slavename\": \"TestSlavename\", \"workdir\": \"/path/to/workdir/TestSlavename\"}",
       "--annotate=gtest",
       "--test-type=base_unittests",
       "--test-launcher-summary-output",
       "/path/to/tmp/json",
       "--builder-name=CrWinGoma",
       "--slave-name=TestSlavename",
       "--build-number=571",
       "base_unittests"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "base_unittests"
   },
   {
     "allow_subannotations": true,
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/runtest.py",
       "--target",
       "Release",
       "--xvfb",
       "--factory-properties",
       "{\"blamelist\": [\"cool_dev1337@chromium.org\", \"hax@chromium.org\"], \"buildername\": \"CrWinGoma\", \"buildnumber\": 571, \"mastername\": \"chromium.fyi\", \"recipe\": \"chromium\", \"slavename\": \"TestSlavename\", \"workdir\": \"/path/to/workdir/TestSlavename\"}",
       "--build-properties",
       "{\"blamelist\": [\"cool_dev1337@chromium.org\", \"hax@chromium.org\"], \"buildername\": \"CrWinGoma\", \"buildnumber\": 571, \"mastername\": \"chromium.fyi\", \"recipe\": \"chromium\", \"slavename\": \"TestSlavename\", \"workdir\": \"/path/to/workdir/TestSlavename\"}",
       "--annotate=gtest",
       "--test-type=content_unittests",
       "--test-launcher-summary-output",
       "/path/to/tmp/json",
       "--builder-name=CrWinGoma",
       "--slave-name=TestSlavename",
       "--build-number=571",
       "content_unittests"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "content_unittests"
   },
   {
     "name": "$final_result",
     "reason": "1 tests failed: ['diagnose_goma']",
     "status_code": 1
   }
 ]