Increase sharding for Site Isolation Android

The bot has been running into test timeouts, so increase the number of
shards used to run tests. Might adjust the exact number of shards after.

Bug: 905842
Change-Id: Icf0ab65e70a0b48b7b97e95318ecabdac31d63aa
Reviewed-on: https://chromium-review.googlesource.com/c/1338569Reviewed-by: Ben Pastene <bpastene@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: Stephen Martinis <martiniss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608622}

testing/buildbot/chromium.fyi.json

@@ -2090,7 +2090,8 @@
               "os": "Android"
             }
           ],
-          "hard_timeout": 960
+          "hard_timeout": 960,
+          "shards": 5
         },
         "test": "components_unittests"
       },
@@ -2109,7 +2110,7 @@
             }
           ],
           "hard_timeout": 960,
-          "shards": 6
+          "shards": 10
         },
         "test": "content_browsertests"
       },

testing/buildbot/test_suites.pyl

@@ -2218,6 +2218,9 @@
         'args': [
           '--site-per-process',
         ],
+        'swarming': {
+          'shards': 5,
+        },
         'test': 'components_unittests',
       },
       'site_per_process_content_browsertests': {
@@ -2225,7 +2228,7 @@
           '--site-per-process'
         ],
         'swarming': {
-          'shards': 6,
+          'shards': 10,
         },
         'test': 'content_browsertests',
       },