[Android] Update existing uses of now-deprecated --test-arguments.

testing/buildbot/chromium.fyi.json

 {
   "Android Asan Builder Tests (dbg)": {
     "gtest_tests": [
       {
         "args": [
           "--tool=asan"
         ],
         "swarming": {
           "can_use_on_swarming_builders": false
         },
@@ skipping 11870 matching lines @@
               "device_type": "bullhead"
             }
           ],
           "hard_timeout": 960
         },
         "test": "content_browsertests"
       },
       {
         "args": [
           "--gtest-filter-file=../../testing/buildbot/filters/site-per-process.content_browsertests.filter",
-          "--test-arguments=--site-per-process"
+          "--site-per-process"
         ],
         "name": "site_per_process_content_browsertests",
         "override_isolate_target": "content_browsertests",
         "swarming": {
           "can_use_on_swarming_builders": true,
           "dimension_sets": [
             {
               "android_devices": "4",
               "device_type": "bullhead"
             }
@@ skipping 10 matching lines @@
             {
               "android_devices": "4",
               "device_type": "bullhead"
             }
           ]
         },
         "test": "content_unittests"
       },
       {
         "args": [
-          "--test-arguments=--site-per-process"
+          "--site-per-process"
         ],
         "name": "site_per_process_content_unittests",
         "override_isolate_target": "content_unittests",
         "swarming": {
           "can_use_on_swarming_builders": true,
           "dimension_sets": [
             {
               "android_devices": "4",
               "device_type": "bullhead"
             }
           ]
         },
         "test": "content_unittests"
       },
       {
         "args": [
-          "--test-arguments=--site-per-process"
+          "--site-per-process"
         ],
         "name": "site_per_process_components_browsertests",
         "override_isolate_target": "components_browsertests",
         "swarming": {
           "can_use_on_swarming_builders": true,
           "dimension_sets": [
             {
               "android_devices": "4",
               "device_type": "bullhead"
             }
           ]
         },
         "test": "components_browsertests"
       },
       {
         "args": [
-          "--test-arguments=--site-per-process"
+          "--site-per-process"
         ],
         "name": "site_per_process_components_unittests",
         "override_isolate_target": "components_unittests",
         "swarming": {
           "can_use_on_swarming_builders": true,
           "dimension_sets": [
             {
               "android_devices": "4",
               "device_type": "bullhead"
             }
@@ skipping 1230 matching lines @@
       },
       {
         "swarming": {
           "can_use_on_swarming_builders": false
         },
         "test": "views_unittests"
       }
     ]
   }
 }