[android] support more system font names

[jonathanpeppers]

Context: #10713
Context: https://github.com/supershopping/ShellFlyoutLagging
Fixes #13239

In reviewing the above customer sample, I noticed time spent in:

79.52ms microsoft.maui!Microsoft.Maui.Handlers.LabelHandler.MapFont(Microsoft.Maui.Handlers.ILabelHandler,Microsoft.Maui.ILabel)
20.71ms microsoft.extensions.logging.abstractions!Microsoft.Extensions.Logging.LoggerExtensions.LogWarning(Microsoft.Extensions

What warning are we trying to log? It seems like it is impacting the time it takes for the first Shell flyout to open.

Adding more logging, I found:

06-19 15:31:19.834  5706  5706 I DOTNET  : Unable to load font 'sans-serif-medium' from assets.
06-19 15:31:19.840  5706  5706 I DOTNET  : Unable to load font 'sans-serif-medium.ttf' from assets.
06-19 15:31:19.840  5706  5706 I DOTNET  : Unable to load font 'Fonts/sans-serif-medium.ttf' from assets.
06-19 15:31:19.841  5706  5706 I DOTNET  : Unable to load font 'fonts/sans-serif-medium.ttf' from assets.
06-19 15:31:19.841  5706  5706 I DOTNET  : Unable to load font 'sans-serif-medium.otf' from assets.
06-19 15:31:19.842  5706  5706 I DOTNET  : Unable to load font 'Fonts/sans-serif-medium.otf' from assets.
06-19 15:31:19.842  5706  5706 I DOTNET  : Unable to load font 'fonts/sans-serif-medium.otf' from assets.

Which is likely just trying to load one of:

• maui/src/Controls/src/Core/Shell/BaseShellItem.cs

  Line 517 in 0543e03

  defaultLabelClass.Setters.Add(new Setter { Property = Label.FontFamilyProperty, Value = "sans-serif-medium" });

• maui/src/Controls/src/Core/Compatibility/Handlers/Shell/Android/ShellItemRenderer.cs

  Line 248 in 0543e03

  .GetTypeface(Font.OfSize("sans-serif-medium", 0.0));

In 2d354d1, we added support for certain Android system fonts. I think we should just expand this further to support various Android fonts like:

sans-serif-black
sans-serif-condensed
sans-serif-condensed-light
sans-serif-light
sans-serif-medium

You can use these in Android such as:

android:fontFamily="sans-serif-medium"

We can load this Typeface from C# such as:

Typeface.Create("sans-serif-medium", TypefaceStyle.Normal)

See: https://stackoverflow.com/a/14344132

In MAUI apps, customers are likely using a Fonts/ folder, so if they use these names, they are likely trying to load a system font.

After these changes, I see this result on a Pixel 5:

Before:
79.52ms microsoft.maui!Microsoft.Maui.Handlers.LabelHandler.MapFont(Microsoft.Maui.Handlers.ILabelHandler,Microsoft.Maui.ILabel)
After:
26.91ms microsoft.maui!Microsoft.Maui.Handlers.LabelHandler.MapFont(Microsoft.Maui.Handlers.ILabelHandler,Microsoft.Maui.ILabel)

So, I think this saves ~52ms of time for the first Shell flyout opening in this sample.

[jonathanpeppers]

I think the font on the flyout menu in this app looks exactly the same: