Tests for Engine ensuring debug-mode apps are attached on iOS.

[sjindel-google]

This PR contains the tests for flutter/engine#10186.

[codecov]

Codecov Report

Merging #37043 into master will increase coverage by 1.12%.
The diff coverage is 50%.

@@            Coverage Diff             @@
##           master   #37043      +/-   ##
==========================================
+ Coverage   54.21%   55.33%   +1.12%     
==========================================
  Files         191      190       -1     
  Lines       17788    17567     -221     
==========================================
+ Hits         9644     9721      +77     
+ Misses       8144     7846     -298

Flag	Coverage Δ
#flutter_tool	55.33% <50%> (+1.12%)	⬆️

Impacted Files	Coverage Δ
packages/flutter_tools/lib/src/ios/devices.dart	36.92% <0%> (+0.26%)	⬆️
packages/flutter_tools/lib/src/commands/drive.dart	75% <100%> (+0.42%)	⬆️
packages/flutter_tools/lib/src/android/gradle.dart	18.94% <0%> (-23.48%)	⬇️
packages/flutter_tools/lib/src/services.dart	0% <0%> (ø)	⬆️
packages/flutter_tools/lib/src/build_info.dart	69.61% <0%> (ø)	⬆️
...utter_tools/lib/src/build_runner/build_script.dart	0% <0%> (ø)	⬆️
...flutter_tools/lib/src/vmservice_record_replay.dart	0% <0%> (ø)	⬆️
...ackages/flutter_tools/lib/src/android/android.dart
...lutter_tools/lib/src/commands/update_packages.dart	3.9% <0%> (+0.27%)	⬆️
packages/flutter_tools/lib/src/doctor.dart	70.18% <0%> (+0.3%)	⬆️
... and 80 more

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[sjindel-google]

I don't think the patch coverage is meaningful here because these tests can only run on devicelab and not in the CI tests.

[jonahwilliams]

LGTM

Yes I wouldn't worry about the patch coverage

[sjindel-google]

@chinmaygarde Chinmay, could you please take another look at this one?