[Android] Cache typefaces in font image source handler (#6470)
authorTomasz Ścisłowicz <toomasz@users.noreply.github.com>
Fri, 16 Aug 2019 18:43:30 +0000 (20:43 +0200)
committerSamantha Houts <samhouts@users.noreply.github.com>
Fri, 16 Aug 2019 18:43:30 +0000 (11:43 -0700)
commitc7b7429e27f555bd5a4c896f47ab476d0a28b326
treedf736334d1d302438cbfd5bb1fab67194268ea7a
parent421c24dc67e8125048ac35374de17c7a99a16b8c
[Android] Cache typefaces in font image source handler (#6470)

* cache typefaces in font image source handler

* remove private modifier

* use concurrent dictionary

* move caching to FontExtensions

* convert null fontFamily parameter to empty string
fixes #6317
fixes #6949
Xamarin.Forms.Platform.Android/Renderers/FontExtensions.cs
Xamarin.Forms.Platform.Android/Renderers/FontImageSourceHandler.cs
Xamarin.Forms.Platform.Android/Renderers/ShellItemRenderer.cs