Support for allowFontScaling in Text

[intergalacticspacehighway]

We can add support for allowFontScaling in the Text component just like React Native (iOS/Android).

This can be really helpful if we want to consider the user's preferred font settings.
We can have allowFontScaling true by default just like RN and convert px to rems just like Stylex.

For e.g.
fontSize: 10 becomes fontSize: "0.625rem". (Considering 16px as base size)
Watch this for a better explanation - https://youtu.be/9JZHodNR184?t=506

I can write a POC this weekend and share some findings. :D

[intergalacticspacehighway]

This is how I think we can make it work. I haven't checked the affected areas yet. I really think we can do better. This is just to give an idea. I also tested the example. The font scaling works with this when changing the browser font settings 😄

[intergalacticspacehighway]

if (props.allowFontScaling && props.style && props.style.fontSize && typeof props.style.fontSize === 'number') {
    const maxFontSize = props.style.fontSize * maxFontSizeMultiplier
    props.style.fontSize = `min(${pxToRemWithBase16(props.style.fontSize)}, ${maxFontSize}px)`;
  } 

We can also add support for maxFontSizeMultiplier 😅 (Won't work on IE11, so maybe not a great idea).