Refactor external_ui → external_textures

[matanlurey]

This PR makes no behavioral changes to executed code, and instead focuses on organization and naming:

1. Almost¹ anything named external_ui is renamed external_textures
2. Extended the README to explain the intent of the test, as well as how to run it
3. Renamed main.dart and main_test.dart to frame_rate_main.dart and frame_rate_test.dart (we'll add more)
4. Did some refactoring of the test to make it more obvious what is being asserted (i.e. widgetBuilds and friends)

Given how complex (and in-flux) this directory is, I'm also requesting either John, Jonah or I review any changes.

Footnotes

1. Except the name of the .ci.yaml task, i.e. name: Linux_pixel_7pro external_ui_integration_test because I'm apparently not able to change that without creating a new task as bringup: true and playing a bit of a dance. Maybe that's worth doing though (in future PRs)? ↩

[matanlurey]

Ping @jonahwilliams just because I've never touched these files before :)

[matanlurey]

/cc @jmagman as well (again, no behavioral impact - but names are changing!)

[jonahwilliams]

I think this will work, but I've never renamed a devicelab task before.

LGTM

[keyonghan]

This will affect the benchmark metrics as they are tied to task_name. If this is the way to go, you may want to give engine people a heads up. /cc @zanderso

[matanlurey]

These aren't benchmarks confusingly.

[zanderso]

lgtm

[zanderso]

I believe this is only cosmetic, but I'd suggest keeping the task_name and the name field above matching. So the name above on line 2171 would change to Linux_pixel_7pro external_textures_integration_test.

[matanlurey]

Unfortunately I can't do that in a single PR because you can only rename a task by starting it as bringup: true. I can do that but I'll need a few more PRs.

[eliasyishak]

Reverting due to errors in post submit

Example of builder erroring out: https://ci.chromium.org/ui/p/flutter/builders/prod/Mac_ios%20external_ui_integration_test_ios/9562/overview

Sample error

[2024-01-24 13:06:08.688564] [STDOUT] stdout: [  +59 ms] Artifact Instance of 'FlutterWebSdk' is not required, skipping update.
[2024-01-24 13:06:08.688645] [STDOUT] stdout: [        ] Artifact Instance of 'LegacyCanvasKitRemover' is not required, skipping update.
[2024-01-24 13:06:08.689204] [STDOUT] stdout: [        ] Artifact Instance of 'WindowsEngineArtifacts' is not required, skipping update.
[2024-01-24 13:06:08.689265] [STDOUT] stdout: [        ] Artifact Instance of 'MacOSEngineArtifacts' is not required, skipping update.
[2024-01-24 13:06:08.689301] [STDOUT] stdout: [        ] Artifact Instance of 'LinuxEngineArtifacts' is not required, skipping update.
[2024-01-24 13:06:08.689334] [STDOUT] stdout: [        ] Artifact Instance of 'LinuxFuchsiaSDKArtifacts' is not required, skipping update.
[2024-01-24 13:06:08.689403] [STDOUT] stdout: [        ] Artifact Instance of 'MacOSFuchsiaSDKArtifacts' is not required, skipping update.
[2024-01-24 13:06:08.689442] [STDOUT] stdout: [        ] Artifact Instance of 'FlutterRunnerSDKArtifacts' is not required, skipping update.
[2024-01-24 13:06:08.689475] [STDOUT] stdout: [        ] Artifact Instance of 'FlutterRunnerDebugSymbols' is not required, skipping update.
[2024-01-24 13:06:08.707419] [STDOUT] stdout: [  +17 ms] "flutter drive" took 20,989ms.
[2024-01-24 13:06:08.713860] [STDOUT] stderr: [   +4 ms] Target file "lib/main.dart" not found.
[2024-01-24 13:06:08.714128] [STDOUT] stderr: [   +1 ms] 
[2024-01-24 13:06:08.714185] [STDOUT] stderr:            #0      FlutterCommand.validateCommand (package:flutter_tools/src/runner/flutter_command.dart:1858:9)
[2024-01-24 13:06:08.714228] [STDOUT] stderr:            #1      DriveCommand.validateCommand (package:flutter_tools/src/commands/drive.dart:227:18)
[2024-01-24 13:06:08.714263] [STDOUT] stderr:            #2      FlutterCommand.verifyThenRunCommand (package:flutter_tools/src/runner/flutter_command.dart:1713:11)
[2024-01-24 13:06:08.714294] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.714325] [STDOUT] stderr:            #3      FlutterCommand.run.<anonymous closure> (package:flutter_tools/src/runner/flutter_command.dart:1398:27)
[2024-01-24 13:06:08.714357] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.714459] [STDOUT] stderr:            #4      AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:153:19)
[2024-01-24 13:06:08.714527] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.714562] [STDOUT] stderr:            #5      CommandRunner.runCommand (package:args/command_runner.dart:212:13)
[2024-01-24 13:06:08.714594] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.714625] [STDOUT] stderr:            #6      FlutterCommandRunner.runCommand.<anonymous closure> (package:flutter_tools/src/runner/flutter_command_runner.dart:355:9)
[2024-01-24 13:06:08.714656] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.714686] [STDOUT] stderr:            #7      AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:153:19)
[2024-01-24 13:06:08.714717] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.714747] [STDOUT] stderr:            #8      FlutterCommandRunner.runCommand (package:flutter_tools/src/runner/flutter_command_runner.dart:295:5)
[2024-01-24 13:06:08.714777] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.714899] [STDOUT] stderr:            #9      run.<anonymous closure>.<anonymous closure> (package:flutter_tools/runner.dart:119:9)
[2024-01-24 13:06:08.714943] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.714976] [STDOUT] stderr:            #10     AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:153:19)
[2024-01-24 13:06:08.715012] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.715043] [STDOUT] stderr:            #11     main (package:flutter_tools/executable.dart:90:3)
[2024-01-24 13:06:08.715100] [STDOUT] stderr:            <asynchronous suspension>
[2024-01-24 13:06:08.715183] [STDOUT] stderr: 
[2024-01-24 13:06:08.715238] [STDOUT] stderr: 
[2024-01-24 13:06:08.715324] [STDOUT] stdout: [        ] ensureAnalyticsSent: 0ms
[2024-01-24 13:06:08.715362] [STDOUT] stdout: [        ] Running 1 shutdown hook
[2024-01-24 13:06:08.715392] [STDOUT] stdout: [        ] Shutdown hooks complete
[2024-01-24 13:06:08.715422] [STDOUT] stdout: [        ] exiting with code 1

[yusuf-goog]

@eliasyishak do you need to add the revert label to this issue?

[eliasyishak]

Yep it was my mistake to open that other PR manually @yusuf-goog, the bot already created a new PR and reverted this change