Mac tool_integration_tests_4_4 is 1.79% flaky

[fluttergithubbot]

The post-submit test builder Mac tool_integration_tests_4_4 had a flaky ratio 1.79% for the past 15 days, which is the flakist test below 2.00% threshold.

One recent flaky example for a same commit: https://ci.chromium.org/ui/p/flutter/builders/prod/Mac%20tool_integration_tests_4_4/715
Commit: flutter@ae97666
Failed build:

https://ci.chromium.org/ui/p/flutter/builders/prod/Mac%20tool_integration_tests_4_4/715
https://ci.chromium.org/ui/p/flutter/builders/prod/Mac%20tool_integration_tests_4_4/700
https://ci.chromium.org/ui/p/flutter/builders/prod/Mac%20tool_integration_tests_4_4/661

Succeeded build (3 most recent):

https://ci.chromium.org/ui/p/flutter/builders/prod/Mac%20tool_integration_tests_4_4/814
https://ci.chromium.org/ui/p/flutter/builders/prod/Mac%20tool_integration_tests_4_4/813
https://ci.chromium.org/ui/p/flutter/builders/prod/Mac%20tool_integration_tests_4_4/812

Please follow https://github.com/flutter/flutter/wiki/Reducing-Test-Flakiness#fixing-flaky-tests to fix the flakiness and enable the test back after validating the fix (internal dashboard to validate: go/flutter_test_flakiness).