fix style attribute space

[NiuGuohui]

Summary

When the svg code has some blank in style attribute,like this style="white-space: pre; "
it was throw an error Cannot read property 'trim' of undefined.

Test Plan

Test Svg Code:

<?xml version="1.0" encoding="UTF-8" standalone="no" ?><!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd"><svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1" width="1119" height="286.47938144329896" viewBox="0 0 1119 286.47938144329896" xml:space="preserve"><g transform="matrix(1 0 0 1 296.43 94.71)" style=""  ><text xml:space="preserve" font-family="Times New Roman" font-size="48" font-style="normal" font-weight="normal" style="stroke: none; stroke-width: 1; stroke-dasharray: none; stroke-linecap: butt; stroke-dashoffset: 0; stroke-linejoin: miter; stroke-miterlimit: 4; fill: rgb(255,0,0); fill-rule: nonzero; opacity: 1; white-space: pre;" ><tspan x="-168" y="15.08" style="white-space: pre; ">some text</tspan></text></g></svg>

What's required for testing (prerequisites)?

What are the steps to reproduce (after prerequisites)?

Compatibility

OS	Implemented
iOS	✅
Android	✅

Checklist

• I have tested this on a device and a simulator
• I added documentation in README.md
• I updated the typed files (typescript)
• I added a test for the API in the __tests__ folder

[WoLewicki]

LGTM! Thanks for your contribution 🎉