* Allow for gradle downloading missing SDK assets if SDK licenses are present.

*  Improvements for windows testing

This reverts commit 6f5e88a5.

* Allow for gradle downloading missing SDK assets if SDK licenses are present.

* Fix license path for missing sdkmanager

* Cirrus re-run...

* Fix condition check

* rename props, add docs, rename method

* fix tests after param changes

* Fix weird path for flutter run and add tests

* remove print, fix tests

* Detect Android SDK 28/28.0.3

* revert minimumAndroidSdkVersion const change

These are essentially self-inflicted race conditions. Instead of timeouts we're going to try a more verbose logging mechanism that points out when things are taking a long time.

This reverts commit 76f70810.

* Remove many timeouts.

These are essentially self-inflicted race conditions. Instead of timeouts we're going to try a more verbose logging mechanism that points out when things are taking a long time.

* Get the attach tests to pass.

* Apply review comments from Todd

* More review comment fixes

* Put back the extended timeouts here now that I know why we have them...

* Fall back to ANDROID_SDK_ROOT if ANDROID_HOME is not set

And update descriptions to use the non-deprecated ANDROID_SDK_ROOT.

Fixes #15114.

* Remove trailing whitespace

* Update dev/devicelab/lib/framework/adb.dart
Co-Authored-By: DanTup <danny@tuppeny.com>

* Reformat long line

Fixes #24750.

* updated Flutter Doctor grammar

* updated messaging based on a suggestion by Greg Spencer

* grammar update

This is a cleanup PR.

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

* First step in Flutter Doctor refactor. Assigns categories to all validators.

* Revert "Roll engine e54bc4ea1832..a84b210b3d26 (6 commits) (#20453)"

This reverts commit 05c2880a.

* Split iOS and Android workflows into workflow and validator classes.

* Change ValidatorCategory to handle standalone validators that share a
category (e.g. IntelliJ).

Also make Android Studio and Android toolchain use separate categories.

At this stage, flutter doctor output matches what it was previously.
(The summary() method itself has not yet been changed )

* Change doctor summary code to support validator categories.

Output is still unchanged.

* Handle small formatting issues.

* Flip Flutter category's isGroup field to false until it's actually
needed.

* Revert auto-generated formatting changes to keep those lines from
muddying the pull.

* Small fixes pointed out by analyzer.

* Properly fix analyzer issues around const constructors.

* Small changes to address comments.

* Add tests to verify grouped validator behavior and validationtype
merging.

* Update doctor.dart

* Add comments for clarification.

This is an attempt to reland #18488 with less breakage on macOS.

Our style guide says the k's are not necessary, and it seems like a good idea to make all the code be consistent on this.

Only naming changes to private vars: no logic changes.

* Search for a suitable ARM sysroot instead of hardcoding it;
* Add facility to explain why NDK was not found;

Very basic support for "flutter emulators" which just lists the available Android AVDs.

Relates to:

https://github.com/flutter/flutter/issues/14822
https://github.com/Dart-Code/Dart-Code/issues/490
https://github.com/flutter/flutter/issues/13379

Fixes https://github.com/flutter/flutter/issues/16332

This updates AppContext per the recommendations in #15352

Fixes #15352

* Revert "Revert "Add android license verification to doctor and some refactoring" (#14727)"

This reverts commit d2602947.

* Add tests, fix sdkManagerEnv and use it consistently, and rearrange Status object model

* AnsiSpinner needs to leave the cursor where it found it.

* fix tests

* Const constructor warning only shows up on windows...?

* Avoid crash if we can't find the home directory

* Make pathVarSeparator return a string in the mock

* Implement review comments

* Fix out-of-order problem on stop

Reports from that commit included:

* Doctor hanging
* Doctor prompting to install JDK
* AnsiStatus.cancel() printing elapsed time and extra newline
* Printing extra spinner character at the end of each line

* Initial version, seems to work

* Unit test for android license checker

* Cleanups

* Windows analyzer wants const.

* Refinements to timeout

* review comments

* Forgot a nit

flutter doctor --android-licenses requires Android sdkmanager version 26
or later. When sdkmanager is not available (SDKs earlier than v25),
direct users to SDK upgrade instructions. When it's installed but not
v26 or later, emit instructions to run sdkmanager --update.

Convenience getters for the the path to the Android SDK manager and the
currently installed version of the tool.

Pre-factoring to support better checks around the --android-licenses
command, which uses a feature of the SDK manager that is unsupported in
older versions of the tool.