iOS: Update device testing configuration

tools_webrtc/ios/internal.tryserver.webrtc/ios_arm64.json

Index: tools_webrtc/ios/internal.tryserver.webrtc/ios_arm64.json
diff --git a/tools_webrtc/ios/internal.tryserver.webrtc/ios_arm64.json b/tools_webrtc/ios/internal.tryserver.webrtc/ios_arm64.json
index 37074b6f3e89ca71bd4f176684b58323fec2c0ff..6f3d0b781df71da390f9c5b59df2dd15a6cd2fec 100644
--- a/tools_webrtc/ios/internal.tryserver.webrtc/ios_arm64.json
+++ b/tools_webrtc/ios/internal.tryserver.webrtc/ios_arm64.json
@@ -5,20 +5,25 @@
   "xcode version": "8.0",
   "gn_args": [
     "goma_dir=\"$(goma_dir)\"",
+    "additional_target_cpus=[\"arm\"]",
     "is_component_build=false",
     "is_debug=true",
-    "target_cpu=\"x64\"",
+    "target_cpu=\"arm64\"",
     "target_os=\"ios\"",
     "use_goma=true"
   ],
+  "env": {
+    "MAC_TOOLCHAIN_REVISION": "8E2002-1"
+  },
   "use_analyze": false,
   "additional_compile_targets": [ "all" ],
   "configuration": "Debug",
+  "bucket": "chromium-webrtc",
   "tests": [
     {
-      "include": "common_tests.json",
+      "app": "modules_unittests",
       "device type": "iPhone 6s",
-      "os": "10.0"
+      "os": "10.0.1"
     }
   ]
 }