Auto merge of #16759 - glennw:subpixel, r=cbrewster
Auto merge of #16759 - glennw:subpixel, r=cbrewster

Enable subpixel anti-aliasing on text by default.

No doubt there are still some bugs and missing features related to subpixel text anti-aliasing.

But enabling by default should allow us to detect these and fix them.

If we run into any major issues, this is a standalone commit that can be reverted while we fix the problem.

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