Revert "tools/perf: Disable rendering.mobile/microgame_fps on android pixel2"

This reverts commit 398eae2c.

Reason for revert: The underlying issue has been fixed, re-enabling
                   the test.

Original change's description:
> tools/perf: Disable rendering.mobile/microgame_fps on android pixel2
>
> Change-Id: I4cfb20bd12e93c84bddb0ff7920e718c0fc03fc4
> No-Try: True
> Tbr: wenbinzhang@google.com
> Bug: 1166558
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2626299
> Reviewed-by: Eric Seckler <eseckler@chromium.org>
> Commit-Queue: Eric Seckler <eseckler@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#843462}

TBR=eseckler@chromium.org,chromium-scoped@luci-project-accounts.iam.gserviceaccount.com,wenbinzhang@google.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1166558
Change-Id: I2df7afa204ef888d6bddd6340f979165e91ed501
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2632667Reviewed-by: Benoit L <lizeb@chromium.org>
Reviewed-by: Eric Seckler <eseckler@chromium.org>
Commit-Queue: Benoit L <lizeb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#844049}

tools/perf/expectations.config

@@ -254,7 +254,6 @@ crbug.com/1160628 [ android-pixel-2 ] rendering.mobile/idle_power_css_animation
 crbug.com/1160628 [ android-pixel-2 ] rendering.mobile/idle_power_request_animation_frame [ Skip ]
 crbug.com/1160628 [ android-pixel-2 ] rendering.mobile/idle_power_set_timeout_long [ Skip ]
 crbug.com/1160628 [ android-pixel-2 ] rendering.mobile/idle_power_set_timetout [ Skip ]
-crbug.com/1166558 [ android-pixel-2 ] rendering.mobile/microgame_fps [ Skip ]
 
 # Benchmark: rasterize_and_record_micro.top_25
 crbug.com/764543 rasterize_and_record_micro.top_25/file://static_top_25/wikipedia.html [ Skip ]