[CT] Use zips of SKPs to speed up "isolate tests" in recipes

scripts/slave/recipes/skia/ct_skps.expected/CT_DM_1m_SKPs.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "RECIPE_PACKAGE[depot_tools]/gclient.py",
       "config",
       "--spec",
       "cache_dir = None\nsolutions = [{'deps_file': 'DEPS', 'managed': True, 'name': 'skia', 'url': 'https://skia.googlesource.com/skia.git'}, {'deps_file': 'DEPS', 'managed': True, 'name': 'src', 'url': 'https://chromium.googlesource.com/chromium/src.git'}]"
     ],
@@ skipping 227 matching lines @@
       "gs://cluster-telemetry/skps/All/57259e0-05dcb4c/slave1",
       "[SLAVE_BUILD]/skps/slave1"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "gsutil rsync"
   },
   {
     "cmd": [
       "python",
       "-u",
+      "RECIPE_MODULE[build::zip]/resources/zip.py"
+    ],
+    "cwd": "[SLAVE_BUILD]",
+    "name": "zip skps dir",
+    "stdin": "{\"entries\": [{\"path\": \"[SLAVE_BUILD]/skps/slave1\", \"type\": \"dir\"}], \"output\": \"[SLAVE_BUILD]/skps/slave1.zip\", \"root\": \"[SLAVE_BUILD]/skps/slave1\", \"use_python_zip\": false}"
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
       "\nimport sys, os\npath = sys.argv[1]\nmode = int(sys.argv[2])\nif not os.path.isdir(path):\n  if os.path.exists(path):\n    print \"%s exists but is not a dir\" % path\n    sys.exit(1)\n  os.makedirs(path, mode)\n",
       "[SLAVE_BUILD]/swarming_temp_dir",
       "511"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "makedirs swarming tmp dir",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import sys, os@@@",
       "@@@STEP_LOG_LINE@python.inline@path = sys.argv[1]@@@",
@@ skipping 55 matching lines @@
       "gs://cluster-telemetry/skps/All/57259e0-05dcb4c/slave2",
       "[SLAVE_BUILD]/skps/slave2"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "gsutil rsync (2)"
   },
   {
     "cmd": [
       "python",
       "-u",
+      "RECIPE_MODULE[build::zip]/resources/zip.py"
+    ],
+    "cwd": "[SLAVE_BUILD]",
+    "name": "zip skps dir (2)",
+    "stdin": "{\"entries\": [{\"path\": \"[SLAVE_BUILD]/skps/slave2\", \"type\": \"dir\"}], \"output\": \"[SLAVE_BUILD]/skps/slave2.zip\", \"root\": \"[SLAVE_BUILD]/skps/slave2\", \"use_python_zip\": false}"
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
       "\nimport sys, os\npath = sys.argv[1]\nmode = int(sys.argv[2])\nif not os.path.isdir(path):\n  if os.path.exists(path):\n    print \"%s exists but is not a dir\" % path\n    sys.exit(1)\n  os.makedirs(path, mode)\n",
       "[SLAVE_BUILD]/swarming_temp_dir",
       "511"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "makedirs swarming tmp dir (2)",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import sys, os@@@",
       "@@@STEP_LOG_LINE@python.inline@path = sys.argv[1]@@@",
@@ skipping 55 matching lines @@
       "gs://cluster-telemetry/skps/All/57259e0-05dcb4c/slave3",
       "[SLAVE_BUILD]/skps/slave3"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "gsutil rsync (3)"
   },
   {
     "cmd": [
       "python",
       "-u",
+      "RECIPE_MODULE[build::zip]/resources/zip.py"
+    ],
+    "cwd": "[SLAVE_BUILD]",
+    "name": "zip skps dir (3)",
+    "stdin": "{\"entries\": [{\"path\": \"[SLAVE_BUILD]/skps/slave3\", \"type\": \"dir\"}], \"output\": \"[SLAVE_BUILD]/skps/slave3.zip\", \"root\": \"[SLAVE_BUILD]/skps/slave3\", \"use_python_zip\": false}"
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
       "\nimport sys, os\npath = sys.argv[1]\nmode = int(sys.argv[2])\nif not os.path.isdir(path):\n  if os.path.exists(path):\n    print \"%s exists but is not a dir\" % path\n    sys.exit(1)\n  os.makedirs(path, mode)\n",
       "[SLAVE_BUILD]/swarming_temp_dir",
       "511"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "makedirs swarming tmp dir (3)",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import sys, os@@@",
       "@@@STEP_LOG_LINE@python.inline@path = sys.argv[1]@@@",
@@ skipping 55 matching lines @@
       "gs://cluster-telemetry/skps/All/57259e0-05dcb4c/slave4",
       "[SLAVE_BUILD]/skps/slave4"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "gsutil rsync (4)"
   },
   {
     "cmd": [
       "python",
       "-u",
+      "RECIPE_MODULE[build::zip]/resources/zip.py"
+    ],
+    "cwd": "[SLAVE_BUILD]",
+    "name": "zip skps dir (4)",
+    "stdin": "{\"entries\": [{\"path\": \"[SLAVE_BUILD]/skps/slave4\", \"type\": \"dir\"}], \"output\": \"[SLAVE_BUILD]/skps/slave4.zip\", \"root\": \"[SLAVE_BUILD]/skps/slave4\", \"use_python_zip\": false}"
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
       "\nimport sys, os\npath = sys.argv[1]\nmode = int(sys.argv[2])\nif not os.path.isdir(path):\n  if os.path.exists(path):\n    print \"%s exists but is not a dir\" % path\n    sys.exit(1)\n  os.makedirs(path, mode)\n",
       "[SLAVE_BUILD]/swarming_temp_dir",
       "511"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "makedirs swarming tmp dir (4)",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import sys, os@@@",
       "@@@STEP_LOG_LINE@python.inline@path = sys.argv[1]@@@",
@@ skipping 55 matching lines @@
       "gs://cluster-telemetry/skps/All/57259e0-05dcb4c/slave5",
       "[SLAVE_BUILD]/skps/slave5"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "gsutil rsync (5)"
   },
   {
     "cmd": [
       "python",
       "-u",
+      "RECIPE_MODULE[build::zip]/resources/zip.py"
+    ],
+    "cwd": "[SLAVE_BUILD]",
+    "name": "zip skps dir (5)",
+    "stdin": "{\"entries\": [{\"path\": \"[SLAVE_BUILD]/skps/slave5\", \"type\": \"dir\"}], \"output\": \"[SLAVE_BUILD]/skps/slave5.zip\", \"root\": \"[SLAVE_BUILD]/skps/slave5\", \"use_python_zip\": false}"
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
       "\nimport sys, os\npath = sys.argv[1]\nmode = int(sys.argv[2])\nif not os.path.isdir(path):\n  if os.path.exists(path):\n    print \"%s exists but is not a dir\" % path\n    sys.exit(1)\n  os.makedirs(path, mode)\n",
       "[SLAVE_BUILD]/swarming_temp_dir",
       "511"
     ],
     "cwd": "[SLAVE_BUILD]",
     "name": "makedirs swarming tmp dir (5)",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import sys, os@@@",
       "@@@STEP_LOG_LINE@python.inline@path = sys.argv[1]@@@",
@@ skipping 658 matching lines @@
       "@@@STEP_LOG_END@json.output@@@",
       "@@@STEP_LINK@shard #0 isolated out@blah@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]