* Remove gn. ninja commands from test runner.

* Fix formatting issues.

* Remove trailing space.

* Initialize command variable.

Per gn documentation, the output timestamp can remain the same if all outputs remain the same, resulting in large time savings since dependent targets don't need to be rebuilt.
See: https://gn.googlesource.com/gn/+/HEAD/docs/reference.md#target-declarations-action_declare-a-target-that-runs-a-script-a-single-time-outputs

Currently, `copy_debug_symbols.py` updates timestamps unconditionally, resulting in slower incremental and no-op builds.
We change its current behavior to not update the timestamps if the debug symbols will not change.

Local testing indicates around a `20s` improvement for no-op and incremental builds:
 - Control: http://go/paste/4800062489100288
 - Experiment: http://go/paste/5727928869453824

See https://fxbug.dev/79001.

CC: @naudzghebre 

https://dart.googlesource.com/sdk.git/+log/369366069b83..0796dd6c7bcf

2021-06-17 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.14.0-223.0.dev

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/dart-sdk-flutter-engine
Please CC dart-vm-team@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/master/autoroll/README.md

This reverts commit e274d310.

* Remove autoninja calls from the analyze script.

Calling autoninja from this script is preventing the roll of new depot
tools that requires autoninja to run from inside a goma context.

Bug: https://github.com/flutter/flutter/issues/84618

* Also remove gn commands.

* Comment the gn/ninja commands to build java tests.

* Remove the ninja command.

* Remove steps to build host_debug from tests.

* Assert folder exists.

* Remove outdated code.

* Fix path joining instructions.

This option will be the default in Skia soon. Per discussion in #26067, let’s be explicit about disabling it for the time being, and we can revisit the flag in the future if desirable.

This reverts commit e56dd3a1.

* Adjust order

* Update code

* Fix Extended

* Add tests

* Better constants

* Format

* Comment

* Link

https://skia.googlesource.com/skia.git/+log/af8047dbb849..fab6ede2ec1d

2021-06-16 skia-autoroll@skia-public.iam.gserviceaccount.com Roll Dawn from 2ee28d304f29 to b03adf374711 (9 revisions)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/skia-flutter-autoroll
Please CC jmbetancourt@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/master/autoroll/README.md

TextInputType.none makes it possible to disable the virtual keyboard
for certain TextFields, and lays the foundations for custom in-app
virtual keyboards (flutter/flutter#76072).

Ref: flutter/flutter#83567