Shard & set hard timeout for telemetry_perf_unittests

testing/buildbot/chromium.mac.json

Index: testing/buildbot/chromium.mac.json
diff --git a/testing/buildbot/chromium.mac.json b/testing/buildbot/chromium.mac.json
index 985c01a59e1bec017fa0b60f1094eebd3b74f8a0..6444b0b4501603b8a1bc3d8f3ceeeeb78f00549d 100644
--- a/testing/buildbot/chromium.mac.json
+++ b/testing/buildbot/chromium.mac.json
@@ -873,7 +873,9 @@
           "telemetry_perf_unittests_run"
         ],
         "swarming": {
-          "can_use_on_swarming_builders": true
+          "can_use_on_swarming_builders": true,
+          "hard_timeout": 960,
+          "shards": 12
         }
       },
       {
@@ -1198,7 +1200,9 @@
           "telemetry_perf_unittests_run"
         ],
         "swarming": {
-          "can_use_on_swarming_builders": true
+          "can_use_on_swarming_builders": true,
+          "hard_timeout": 960,
+          "shards": 12
         }
       },
       {
@@ -1523,7 +1527,9 @@
           "telemetry_perf_unittests_run"
         ],
         "swarming": {
-          "can_use_on_swarming_builders": true
+          "can_use_on_swarming_builders": true,
+          "hard_timeout": 960,
+          "shards": 12
         }
       },
       {
@@ -1849,7 +1855,9 @@
           "telemetry_perf_unittests_run"
         ],
         "swarming": {
-          "can_use_on_swarming_builders": true
+          "can_use_on_swarming_builders": true,
+          "hard_timeout": 960,
+          "shards": 12
         }
       },
       {