Not really sure how to improve this further, but should help with cases
like this:
```csharp
[runtime] 2022-06-28 05:32:06 [verbose]: 💨 Class: TestSceneSpectatorPlayback
[runtime] 2022-06-28 05:32:06 [verbose]: 🔶 Test: TestWithSendFailure
[runtime] 2022-06-28 05:32:06 [verbose]: 🔸 Step #1 Setup containers
[runtime] 2022-06-28 05:32:06 [verbose]: Received 1 new frames (total 1 of 2)
[runtime] 2022-06-28 05:32:06 [verbose]: 🔸 Step #2 received frames
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 7 of 8)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 13 of 19)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 19 of 29)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 25 of 44)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 31 of 45)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 37 of 59)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 43 of 67)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 49 of 125)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 55 of 126)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 61 of 127)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 67 of 128)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 73 of 129)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 79 of 130)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 85 of 131)
[runtime] 2022-06-28 05:32:06 [verbose]: ✔️ 22 repetitions
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 91 of 132)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 97 of 133)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 103 of 134)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 109 of 135)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 115 of 136)
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 121 of 137)
[runtime] 2022-06-28 05:32:06 [verbose]: 🔸 Step #3 start failing sends
[runtime] 2022-06-28 05:32:06 [verbose]: Received 6 new frames (total 127 of 138)
[runtime] 2022-06-28 05:32:06 [verbose]: 🔸 Step #4 wait for send attempts
[runtime] 2022-06-28 05:32:06 [verbose]: 🔸 Step #5 frames did not increase
[runtime] 2022-06-28 05:32:06 [verbose]: 💥 Failed
[runtime] 2022-06-28 05:32:06 [verbose]: ⏳ Currently loading components (0)
[runtime] 2022-06-28 05:32:06 [verbose]: 🧵 Task schedulers
[runtime] 2022-06-28 05:32:06 [verbose]: LoadComponentsAsync (standard) concurrency:4 running:0 pending:0
[runtime] 2022-06-28 05:32:06 [verbose]: LoadComponentsAsync (long load) concurrency:4 running:0 pending:0
[runtime] 2022-06-28 05:32:06 [verbose]: 🎱 Thread pool
[runtime] 2022-06-28 05:32:06 [verbose]: worker: min 1 max 32,767 available 32,766
[runtime] 2022-06-28 05:32:06 [verbose]: completion: min 1 max 1,000 available 1,000
[runtime] 2022-06-28 05:32:06 [verbose]: Host execution state changed to Stopping
```
https://teamcity.ppy.sh/buildConfiguration/Osu_Build/811?hideProblemsFromDependencies=false&hideTestsFromDependencies=false&expandBuildTestsSection=true
Not only does this combine the check into one location, but it also adds
a check on the global `WorkingBeatmap` being updated, which is the only
way I can see the following failure happening:
```csharp
05:19:07 osu.Game.Tests: osu.Game.Tests.Visual.Editing.TestSceneEditorBeatmapCreation.TestAddAudioTrack
05:19:07 Failed TestAddAudioTrack [161 ms]
05:19:07 Error Message:
05:19:07 TearDown : System.NullReferenceException : Object reference not set to an instance of an object.
05:19:07 Stack Trace:
05:19:07 --TearDown
05:19:07 at osu.Game.Database.ModelManager`1.<>c__DisplayClass7_0.<AddFile>b__0(TModel managed) in C:\BuildAgent\work\ecd860037212ac52\osu.Game\Database\ModelManager.cs:line 36
05:19:07 at osu.Game.Database.ModelManager`1.<>c__DisplayClass8_0.<performFileOperation>b__0(Realm realm) in C:\BuildAgent\work\ecd860037212ac52\osu.Game\Database\ModelManager.cs:line 49
05:19:07 at osu.Game.Database.RealmExtensions.Write(Realm realm, Action`1 function) in C:\BuildAgent\work\ecd860037212ac52\osu.Game\Database\RealmExtensions.cs:line 14
05:19:07 at osu.Game.Database.ModelManager`1.performFileOperation(TModel item, Action`1 operation) in C:\BuildAgent\work\ecd860037212ac52\osu.Game\Database\ModelManager.cs:line 46
05:19:07 at osu.Game.Database.ModelManager`1.AddFile(TModel item, Stream contents, String filename) in C:\BuildAgent\work\ecd860037212ac52\osu.Game\Database\ModelManager.cs:line 36
05:19:07 at osu.Game.Screens.Edit.Setup.ResourcesSection.ChangeAudioTrack(FileInfo source) in C:\BuildAgent\work\ecd860037212ac52\osu.Game\Screens\Edit\Setup\ResourcesSection.cs:line 115
05:19:07 at osu.Game.Tests.Visual.Editing.TestSceneEditorBeatmapCreation.<TestAddAudioTrack>b__13_0() in C:\BuildAgent\work\ecd860037212ac52\osu.Game.Tests\Visual\Editing\TestSceneEditorBeatmapCreation.cs:line 101
05:19:07 at osu.Framework.Testing.Drawables.Steps.AssertButton.checkAssert()
05:19:07 at osu.Framework.Testing.Drawables.Steps.StepButton.PerformStep(Boolean userTriggered)
05:19:07 at osu.Framework.Testing.TestScene.runNextStep(Action onCompletion, Action`1 onError, Func`2 stopCondition)
```
Refactors `ChatLine` component to use more sensible override properties
and layout using grid container. Moves creation of username component
into its own method to simplify BDL.
Updates padding of base `DrawableChannel` flow padding.
Removes usage of `ChatOverlayDrawableChannel` since it's overrides are
no longer needed.
Updates usage of `StandAloneChatDisplay` to use new override properties
of `DrawableChannel`.
