Recipes: make cwd default to slave_build

scripts/slave/recipes/skia/skia.expected/Test-Win8-MSVC-ShuttleA-CPU-AVX-x86_64-Debug.json

Index: scripts/slave/recipes/skia/skia.expected/Test-Win8-MSVC-ShuttleA-CPU-AVX-x86_64-Debug.json
diff --git a/scripts/slave/recipes/skia/skia.expected/Test-Win8-MSVC-ShuttleA-CPU-AVX-x86_64-Debug.json b/scripts/slave/recipes/skia/skia.expected/Test-Win8-MSVC-ShuttleA-CPU-AVX-x86_64-Debug.json
index c2ccc78cd99c518f6d7e0ccec01b8eb8fc3d3f8e..b32619675b015ae87584db7a9202ee3e90b533dc 100644
--- a/scripts/slave/recipes/skia/skia.expected/Test-Win8-MSVC-ShuttleA-CPU-AVX-x86_64-Debug.json
+++ b/scripts/slave/recipes/skia/skia.expected/Test-Win8-MSVC-ShuttleA-CPU-AVX-x86_64-Debug.json
@@ -36,6 +36,7 @@
       "--spec",
       "cache_dir = None\nsolutions = [{'deps_file': 'DEPS', 'managed': True, 'name': 'skia', 'url': 'https://skia.googlesource.com/skia.git'}]"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "gclient setup"
   },
   {
@@ -53,6 +54,7 @@
       "--output-json",
       "/path/to/tmp/json"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "gclient sync",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
@@ -73,6 +75,7 @@
       "\nimport os\nimport sys\nwith open(sys.argv[1], 'w') as f:\n  f.write(os.path.join(os.path.expanduser('~'), 'src'))\n",
       "/path/to/tmp/"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "get CHROME_PATH",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
@@ -105,6 +108,7 @@
       "[SLAVE_BUILD]\\tmp",
       "511"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "makedirs tmp_dir",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
@@ -127,6 +131,7 @@
       "[SLAVE_BUILD]\\skia\\SKP_VERSION",
       "/path/to/tmp/"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "Get expected SKP_VERSION"
   },
   {
@@ -137,6 +142,7 @@
       "[SLAVE_BUILD]\\tmp\\SKP_VERSION",
       "/path/to/tmp/"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "Get downloaded SKP_VERSION"
   },
   {
@@ -152,6 +158,7 @@
       "cat",
       "gs://chromium-skia-gm/skimage/input/TIMESTAMP_LAST_UPLOAD_COMPLETED"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "gsutil cat TIMESTAMP_LAST_UPLOAD_COMPLETED",
     "stdout": "/path/to/tmp/"
   },
@@ -163,6 +170,7 @@
       "[SLAVE_BUILD]\\tmp\\SKIMAGE_VERSION",
       "/path/to/tmp/"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "Get downloaded SKIMAGE_VERSION"
   },
   {
@@ -172,6 +180,7 @@
       "\nimport os, sys\nfrom common import chromium_utils\n\nif os.path.exists(sys.argv[1]):\n  chromium_utils.RemoveDirectory(sys.argv[1])\n",
       "[SLAVE_BUILD]\\dm"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "rmtree dm",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
@@ -191,6 +200,7 @@
       "[SLAVE_BUILD]\\dm",
       "511"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "makedirs dm",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
@@ -302,6 +312,7 @@
       "--nogpu",
       "--dummy-flags"
     ],
+    "cwd": "[SLAVE_BUILD]",
     "name": "dm"
   },
   {