Enable post-compile test isolation for all CI builders.

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

 [
   {
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/bot_update.py",
       "--master",
       "chromium.mac",
       "--builder",
       "Mac Builder (dbg)",
@@ skipping 73 matching lines @@
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "[DEPOT_TOOLS]/gclient.py",
       "runhooks"
     ],
     "env": {
-      "GYP_DEFINES": "clang=1 component=shared_library gomadir='[BUILD]/goma' target_arch=ia32 test_isolation_mode=archive test_isolation_outdir=https://isolateserver.appspot.com use_goma=1"
+      "GYP_DEFINES": "clang=1 component=shared_library gomadir='[BUILD]/goma' target_arch=ia32 test_isolation_mode=prepare 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.mac.json",
       "/path/to/tmp/json"
@@ skipping 86 matching lines @@
       "browser_tests_run",
       "chrome",
       "chromium_builder_tests"
     ],
     "name": "compile"
   },
   {
     "cmd": [
       "python",
       "-u",
-      "[BUILD]/scripts/slave/recipe_modules/isolate/resources/find_isolated_tests.py",
-      "--build-dir",
-      "[SLAVE_BUILD]/src/out/Debug",
-      "--output-json",
-      "/path/to/tmp/json"
+      "[SLAVE_BUILD]/src/tools/swarming_client/isolate.py",
+      "batcharchive",
+      "--dump-json",
+      "/path/to/tmp/json",
+      "--isolate-server",
+      "https://isolateserver.appspot.com",
+      "--verbose",
+      "[SLAVE_BUILD]/src/out/Debug/browser_tests.isolated.gen.json"
     ],
-    "name": "find isolated tests",
+    "name": "isolate tests",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",
       "@@@STEP_LOG_LINE@json.output@  \"browser_tests\": \"[dummy hash for browser_tests]\"@@@",
       "@@@STEP_LOG_LINE@json.output@}@@@",
       "@@@STEP_LOG_END@json.output@@@",
       "@@@SET_BUILD_PROPERTY@swarm_hashes@{\"browser_tests\": \"[dummy hash for browser_tests]\"}@@@"
     ]
   },
   {
     "allow_subannotations": true,
     "cmd": [
       "python",
       "-u",
       "[BUILD]/scripts/slave/zip_build.py",
       "--target",
       "Debug",
       "--build-url",
       "gs://chromium-mac-archive/chromium.mac/Mac Builder (dbg)",
       "--build_revision",
       "170242",
       "--factory-properties",
       "{\"blamelist\": [\"cool_dev1337@chromium.org\", \"hax@chromium.org\"], \"buildername\": \"Mac Builder (dbg)\", \"buildnumber\": 571, \"mastername\": \"chromium.mac\", \"parent_buildername\": null, \"recipe\": \"chromium\", \"slavename\": \"TestSlavename\", \"workdir\": \"/path/to/workdir/TestSlavename\"}",
       "--build-properties",
       "{\"blamelist\": [\"cool_dev1337@chromium.org\", \"hax@chromium.org\"], \"buildername\": \"Mac Builder (dbg)\", \"buildnumber\": 571, \"mastername\": \"chromium.mac\", \"parent_buildername\": null, \"recipe\": \"chromium\", \"slavename\": \"TestSlavename\", \"workdir\": \"/path/to/workdir/TestSlavename\"}"
     ],
     "name": "package build"
   }
 ]