Reland "Skia: Maintain a checkout on swarming (compile) bots"

scripts/slave/recipes/skia/swarm_test.expected/Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Debug.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "[SLAVE_BUILD]/skia/tools/buildbot_spec.py",
       "/path/to/tmp/json",
       "Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Debug"
     ],
     "cwd": "[SLAVE_BUILD]/skia",
@@ skipping 124 matching lines @@
       "python",
       "-u",
       "\nimport contextlib\nimport math\nimport socket\nimport sys\nimport time\nimport urllib2\n\nHASHES_URL = 'https://gold.skia.org/_/hashes'\nRETRIES = 5\nTIMEOUT = 60\nWAIT_BASE = 15\n\nsocket.setdefaulttimeout(TIMEOUT)\nfor retry in range(RETRIES):\n  try:\n    with contextlib.closing(\n        urllib2.urlopen(HASHES_URL, timeout=TIMEOUT)) as w:\n      hashes = w.read()\n      with open(sys.argv[1], 'w') as f:\n        f.write(hashes)\n        break\n  except Exception as e:\n    print 'Failed to get uninteresting hashes from %s:' % HASHES_URL\n    print e\n    if retry == RETRIES:\n      raise\n    waittime = WAIT_BASE * math.pow(2, retry)\n    print 'Retry in %d seconds.' % waittime\n    time.sleep(waittime)\n",
       "[SLAVE_BUILD]/tmp/uninteresting_hashes.txt"
     ],
     "cwd": "[SLAVE_BUILD]/skia",
     "env": {
       "BUILDTYPE": "Debug",
       "CHROME_HEADLESS": "1",
       "GYP_DEFINES": "skia_arch_type=x86_64 skia_gpu=0 skia_warnings_as_errors=0",
-      "PATH": "[SLAVE_BUILD]/depot_tools:%(PATH)s",
+      "PATH": "[DEPOT_TOOLS]:%(PATH)s",
+      "PYTHONPATH": "[BUILD]/scripts",
       "SKIA_OUT": "[SLAVE_BUILD]/out"
     },
     "name": "get uninteresting hashes",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import contextlib@@@",
       "@@@STEP_LOG_LINE@python.inline@import math@@@",
       "@@@STEP_LOG_LINE@python.inline@import socket@@@",
       "@@@STEP_LOG_LINE@python.inline@import sys@@@",
       "@@@STEP_LOG_LINE@python.inline@import time@@@",
@@ skipping 64 matching lines @@
       "[SLAVE_BUILD]/tmp/uninteresting_hashes.txt",
       "--writePath",
       "[SWARM_OUT_DIR]/dm",
       "--nogpu",
       "--dummy-flags"
     ],
     "env": {
       "BUILDTYPE": "Debug",
       "CHROME_HEADLESS": "1",
       "GYP_DEFINES": "skia_arch_type=x86_64 skia_gpu=0 skia_warnings_as_errors=0",
-      "PATH": "[SLAVE_BUILD]/depot_tools:%(PATH)s",
+      "PATH": "[DEPOT_TOOLS]:%(PATH)s",
+      "PYTHONPATH": "[BUILD]/scripts",
       "SKIA_OUT": "[SLAVE_BUILD]/out"
     },
     "name": "dm"
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]