Update KeyboardToolTipStateMachine.cs

[stumper66]

Fixes # N/A

Proposed changes

• Change nullability on a single function and add null checking.

Customer Impact

• Fixes a NPE that can occur that users have no control over.

Regression?

• No

Risk

• No risk

Test methodology

• It is really hard to reproduce this error. I am unsure how exactly the error occurred but it was a combination of keyboard commands and clicking on various controls.

Test environment(s)

.NET SDK:
Version: 10.0.101
Commit: fad253f51b
Workload version: 10.0.100-manifests.9f71effe
MSBuild version: 18.0.6+fad253f51

Runtime Environment:
OS Name: Windows
OS Version: 10.0.26200
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\10.0.101\

.NET workloads installed:
[maui-windows]
Installation Source: VS 17.14.36603.0, VS 18.1.11312.151
Manifest Version: 10.0.1/10.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\10.0.100\microsoft.net.sdk.maui\10.0.1\WorkloadManifest.json
Install Type: Msi

Configured to use workload sets when installing new manifests.
No workload sets are installed. Run "dotnet workload restore" to install a workload set.

Host:
Version: 10.0.1
Architecture: x64
Commit: fad253f51b

.NET SDKs installed:
8.0.122 [C:\Program Files\dotnet\sdk]
9.0.100-preview.2.24157.14 [C:\Program Files\dotnet\sdk]
9.0.306 [C:\Program Files\dotnet\sdk]
10.0.101 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 8.0.21 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.22 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.0-preview.2.24128.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 10.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 6.0.16 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.36 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.21 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.22 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.0-preview.2.24128.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 10.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 6.0.36 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.21 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.22 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.0-preview.2.24128.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.11 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 10.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
x86 [C:\Program Files (x86)\dotnet]
registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
Not set

global.json file:
Not found

Microsoft Reviewers: Open in CodeFlow

[stumper66]

net 10 NPE.txt

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.40998%. Comparing base (c5d0e05) to head (14a9833).

Additional details and impacted files

@@                   Coverage Diff                   @@
##           release/10.0      #14176          +/-   ##
=======================================================
+ Coverage      77.10412%   97.40998%   +20.30586%     
=======================================================
  Files              3273        1209        -2064     
  Lines            645033      357101      -287932     
  Branches          47701        5584       -42117     
=======================================================
- Hits             497347      347852      -149495     
+ Misses           144005        8462      -135543     
+ Partials           3681         787        -2894     

Flag	Coverage Δ
Debug	97.40998% <ø> (+20.30586%)	⬆️
integration	?
production	?
test	97.40998% <ø> (ø)
unit	?

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