WPF - Use WpfImeKeyboardHandler for supported KeyboardLayoutIds

[amaitland]

Fixes: #1262

Summary:

• Determine which keyboard handler to use based on CurrentInputLanguage

Changes:

• Setup default keyboard handler based on CurrentInputLanguage
• Detect changes in input language

How Has This Been Tested?
Minimal Testing, requires user feedback

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Updated documentation

Checklist:

• Tested the code(if applicable)
• Commented my code
• Changed the documentation(if applicable)
• New files have a license disclaimer
• The formatting is consistent with the project (project supports .editorconfig)

[AppVeyorBot]

✅ Build CefSharp 111.2.20-CI4733 completed (commit 04ba15bbee by @amaitland)

[amaitland]

Make this protected and add xml doc.