[benchmarking] enable dynamic sharding on android-pixel2-perf

Enabling dynamic sharding and increasing iterations of system_health.common_mobile and system_health.memory_mobile

Bug: chromium:1140389
Change-Id: I982596c249f32e0a0a485a97b0f0392c0ea5a8c6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2906787
Reviewed-by: John Chen <johnchen@chromium.org>
Commit-Queue: Wenbin Zhang <wenbinzhang@google.com>
Cr-Commit-Position: refs/heads/master@{#884778}

testing/buildbot/chromium.perf.json

@@ -553,7 +553,8 @@
         "trigger_script": {
           "args": [
             "--multiple-dimension-script-verbose",
-            "True"
+            "True",
+            "--use-dynamic-shards"
           ],
           "requires_simultaneous_shard_dispatch": true,
           "script": "//testing/trigger_scripts/perf_device_trigger.py"

tools/perf/core/perf_data_generator.py

@@ -101,7 +101,9 @@ class TEST_TYPES(object):
 ]
 
 # This is an opt-in list for builders which uses dynamic sharding.
-DYNAMIC_SHARDING_TESTERS = ['android-pixel2-perf-fyi', 'linux-perf-calibration']
+DYNAMIC_SHARDING_TESTERS = [
+    'android-pixel2-perf', 'android-pixel2-perf-fyi', 'linux-perf-calibration'
+]
 
 CALIBRATION_BUILDERS = {
     'linux-perf-calibration': {

tools/perf/cross_device_test_config.py

@@ -32,12 +32,8 @@
         'system_health.memory_mobile': 3,
     },
     'android-pixel2-perf': {
-        'system_health.common_mobile': {
-            # timeToFirstContentfulPaint
-            'browse:media:googleplaystore:2019': 10,
-            'load:social:pinterest:2019': 10,
-            'browse:media:facebook_photos:2019': 10
-        }
+        'system_health.common_mobile': 3,
+        'system_health.memory_mobile': 3,
     },
     'android-go-perf': {
         'system_health.common_mobile': {