Add Mac NDK asset, and fetch NDK on Android compile bots.

infra/bots/recipes/swarm_trigger.expected/Build-Mac-Clang-Arm64-Release-Android.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "\nimport json\nimport sys\n\nwith open(sys.argv[1]) as f:\n  content = json.load(f)\n\nprint json.dumps(content, indent=2)\n",
-      "{\"buildername\": \"Build-Mac-Clang-x86_64-Release\", \"buildnumber\": 5, \"mastername\": \"client.skia\", \"path_config\": \"kitchen\", \"recipe\": \"swarm_trigger\", \"revision\": \"abc123\", \"slavename\": \"skiabot-linux-swarm-000\"}"
+      "{\"buildername\": \"Build-Mac-Clang-Arm64-Release-Android\", \"buildnumber\": 5, \"mastername\": \"client.skia\", \"path_config\": \"kitchen\", \"recipe\": \"swarm_trigger\", \"revision\": \"abc123\", \"slavename\": \"skiabot-linux-swarm-000\"}"
     ],
     "name": "print properties",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@import json@@@",
       "@@@STEP_LOG_LINE@python.inline@import sys@@@",
       "@@@STEP_LOG_LINE@python.inline@@@@",
       "@@@STEP_LOG_LINE@python.inline@with open(sys.argv[1]) as f:@@@",
       "@@@STEP_LOG_LINE@python.inline@  content = json.load(f)@@@",
       "@@@STEP_LOG_LINE@python.inline@@@@",
@@ skipping 236 matching lines @@
       "RECIPE_PACKAGE_REPO[depot_tools]/gsutil.py",
       "----",
       "help"
     ],
     "name": "gsutil help"
   },
   {
     "cmd": [
       "python",
       "-u",
+      "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
+      "[SLAVE_BUILD]/skia/infra/bots/assets/android_sdk/VERSION",
+      "/path/to/tmp/"
+    ],
+    "name": "read android_sdk VERSION"
+  },
+  {
+    "cmd": [
+      "python",
+      "-u",
+      "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
+      "[SLAVE_BUILD]/skia/infra/bots/assets/android_ndk_darwin/VERSION",
+      "/path/to/tmp/"
+    ],
+    "name": "read android_ndk_darwin VERSION"
+  },
+  {
+    "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"
     ],
     "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]@@@",
       "@@@STEP_LOG_LINE@python.inline@mode = int(sys.argv[2])@@@",
@@ skipping 46 matching lines @@
       "trigger",
       "--swarming",
       "https://chromium-swarm.appspot.com",
       "--isolate-server",
       "https://isolateserver.appspot.com",
       "--priority",
       "90",
       "--shards",
       "1",
       "--task-name",
-      "compile_skia/Mac/[dummy has/Build-Mac-Clang-x86_64-Release/5",
+      "compile_skia/Mac/[dummy has/Build-Mac-Clang-Arm64-Release-Android/5",
       "--dump-json",
       "/path/to/tmp/json",
       "--expiration",
       "72000",
       "--io-timeout",
       "2400",
       "--hard-timeout",
       "14400",
       "--dimension",
       "gpu",
       "none",
       "--dimension",
       "os",
       "Mac",
       "--dimension",
       "pool",
       "Skia",
       "--tag",
       "allow_milo:1",
       "--tag",
-      "buildername:Build-Mac-Clang-x86_64-Release",
+      "buildername:Build-Mac-Clang-Arm64-Release-Android",
       "--tag",
       "buildnumber:5",
       "--tag",
       "data:[dummy hash for compile_skia]",
       "--tag",
       "master:client.skia",
       "--tag",
       "name:compile_skia",
       "--tag",
       "os:Mac",
       "--tag",
       "revision:abc123",
       "--tag",
       "slavename:skiabot-linux-swarm-000",
       "--tag",
       "stepname:compile_skia on Mac",
       "--idempotent",
+      "--cipd-package",
+      "android_sdk:skia/bots/android_sdk:version:0",
+      "--cipd-package",
+      "android_ndk_darwin:skia/bots/android_ndk_darwin:version:0",
       "[dummy hash for compile_skia]",
       "--",
       "--workdir",
       "../../..",
       "swarm_compile",
-      "buildername=Build-Mac-Clang-x86_64-Release",
+      "buildername=Build-Mac-Clang-Arm64-Release-Android",
       "mastername=client.skia.compile",
       "buildnumber=1",
       "slavename=skiabot-dummy-compile-slave",
       "reason=Triggered by Skia swarm_trigger Recipe",
       "swarm_out_dir=${ISOLATED_OUTDIR}",
       "revision=abc123"
     ],
     "name": "[trigger] compile_skia on Mac",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
-      "@@@STEP_LOG_LINE@json.output@  \"base_task_name\": \"compile_skia/Mac/[dummy has/Build-Mac-Clang-x86_64-Release/5\", @@@",
+      "@@@STEP_LOG_LINE@json.output@  \"base_task_name\": \"compile_skia/Mac/[dummy has/Build-Mac-Clang-Arm64-Release-Android/5\", @@@",
       "@@@STEP_LOG_LINE@json.output@  \"tasks\": {@@@",
-      "@@@STEP_LOG_LINE@json.output@    \"compile_skia/Mac/[dummy has/Build-Mac-Clang-x86_64-Release/5\": {@@@",
+      "@@@STEP_LOG_LINE@json.output@    \"compile_skia/Mac/[dummy has/Build-Mac-Clang-Arm64-Release-Android/5\": {@@@",
       "@@@STEP_LOG_LINE@json.output@      \"shard_index\": 0, @@@",
       "@@@STEP_LOG_LINE@json.output@      \"task_id\": \"10000\", @@@",
       "@@@STEP_LOG_LINE@json.output@      \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"@@@",
       "@@@STEP_LOG_LINE@json.output@    }@@@",
       "@@@STEP_LOG_LINE@json.output@  }@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@",
       "@@@STEP_LINK@shard #0@https://chromium-swarm.appspot.com/user/task/10000@@@",
       "@@@STEP_LINK@view steps on Milo@https://luci-milo.appspot.com/swarming/task/10000@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[SLAVE_BUILD]/swarming.client/swarming.py",
       "collect",
       "--swarming",
       "https://chromium-swarm.appspot.com",
       "--decorate",
       "--print-status-updates",
       "--json",
-      "{\"base_task_name\": \"compile_skia/Mac/[dummy has/Build-Mac-Clang-x86_64-Release/5\", \"tasks\": {\"compile_skia/Mac/[dummy has/Build-Mac-Clang-x86_64-Release/5\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
+      "{\"base_task_name\": \"compile_skia/Mac/[dummy has/Build-Mac-Clang-Arm64-Release-Android/5\", \"tasks\": {\"compile_skia/Mac/[dummy has/Build-Mac-Clang-Arm64-Release-Android/5\": {\"shard_index\": 0, \"task_id\": \"10000\", \"view_url\": \"https://chromium-swarm.appspot.com/user/task/10000\"}}}",
       "--task-summary-json",
       "/path/to/tmp/json"
     ],
     "name": "compile_skia on Mac",
     "~followup_annotations": [
       "@@@STEP_TEXT@swarming pending 71s@@@",
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"shards\": [@@@",
       "@@@STEP_LOG_LINE@json.output@    {@@@",
       "@@@STEP_LOG_LINE@json.output@      \"abandoned_ts\": null, @@@",
@@ skipping 34 matching lines @@
       "@@@STEP_LINK@shard #0 isolated out@blah@@@",
       "@@@STEP_LINK@view steps on Milo@https://luci-milo.appspot.com/swarming/task/148aa78d7aa0000@@@"
     ]
   },
   {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
   }
 ]