Adding UIA support for toolStripContainer

[Danil-Andrianov]

Partially implements #3421

Proposed changes

• Updated "SupportsUiaProviders" flag.
• Added and implemented toolStripContainer accessible object
• Added unit tests

Customer Impact

Before update:

After update:

Regression?

• No

Risk

• Minimal

Test methodology

• Unit tests
• CTI team

Accessibility testing

• Narrator
• Inspect
• Accessibility Insights

Test environment(s)

• Microsoft Windows [Version 10.0.22000.318]
• .NET Core SDK: 7.0.0-alpha.1.21562.1

Microsoft Reviewers: Open in CodeFlow

[vladimir-krestov]

Looks good if it works

[dreddy-work]

LGTM.

[SergeySmirnov-Akvelon]

LGTM. Please take a look at some minor points.

[Cassie-Li01]

Verified with .NET SDK 7.0.100-preview.3.22124.15 build, this issue is fixed

[ghost]

Hi @Cassie-Li01, it looks like you just commented on a closed PR. The team will most probably miss it.
If you have a question - consider opening a new discussion thread. Alternatively, you'd like to bring something important up to their attention, consider filing a new issue and add enough details to build context.

[John-Qiao]

Verified with .NET SDK 7.0.100-preview.2.22152.5 build, this issue is fixed as same as above test result.

[ghost]

Hi @John-Qiao, it looks like you just commented on a closed PR. The team will most probably miss it.
If you have a question - consider opening a new discussion thread. Alternatively, you'd like to bring something important up to their attention, consider filing a new issue and add enough details to build context.