add md5sum device bin for x86 to dependencies

build/android/devil/devil_dependencies.json

 {
   "config_type": "BaseConfig",
   "dependencies": {
     "aapt": {
       "cloud_storage_bucket": "chromium-telemetry",
       "cloud_storage_base_folder": "binary_dependencies",
       "file_info": {
         "android_host": {
           "cloud_storage_hash": "7448de3cb5e834afdedeaad8b40ba63ac53f3dc4",
           "download_path": "../bin/aapt"
@@ skipping 58 matching lines @@
       "cloud_storage_bucket": "chromium-telemetry",
       "cloud_storage_base_folder": "binary_dependencies",
       "file_info": {
         "android_armeabi-v7a": {
           "cloud_storage_hash": "c8894480be71d5e49118483d83ba7a6e0097cba6",
           "download_path": "../bin/armeabi-v7a/md5sum_device"
         },
         "android_arm64-v8a": {
           "cloud_storage_hash": "bbe410e2ffb48367ac4ca0874598d4f85fd16d9d",
           "download_path": "../bin/arm64-v8a/md5sum_device"
+        },
+        "android_x86": {

[jbudorick, 2015/12/04 21:59:36]

ro.product.cpu.abi comes back with just "x86"?

[bpastene, 2015/12/04 22:03:55]

[ro.product.cpu.abi]: [x86]
[ro.product.cpu.abilist32]: [x86]
[ro.product.cpu.abilist64]: []
[ro.product.cpu.abilist]: [x86]

I think a lot of the properties are manually set by the android-cloud team,
since they don't make a lot of sense on gce machines.

+          "cloud_storage_hash": "b578a5c2c400ce39761e2558cdf2237567a57257",
+          "download_path": "../bin/x86/md5sum_device"
         }
       }
     },
     "md5sum_host": {
       "cloud_storage_bucket": "chromium-telemetry",
       "cloud_storage_base_folder": "binary_dependencies",
       "file_info": {
         "android_host": {
           "cloud_storage_hash": "49e36c9c4246cfebef26cbd07436c1a8343254aa",
           "download_path": "../bin/md5sum_host"
@@ skipping 14 matching lines @@
       "cloud_storage_base_folder": "binary_dependencies",
       "file_info": {
         "android_host": {
           "cloud_storage_hash": "3327881fa3951a503b9467425ea8e781cdffeb9f",
           "download_path": "../bin/split-select"
         }
       }
     }
   }
 }