Merge pull request #1740 from Shopify/textfield-segment-bug

[TextField][Segment] 🔥 will-change causing perf issues

Author: chloerice

UNRELEASED.md

@@ -30,6 +30,7 @@ Use [the changelog guidelines](https://git.io/polaris-changelog-guidelines) to f
 
 - Fixes `monochrome` variant of `Link` and `Button` components to support multi-line link text ([#1686](https://github.com/Shopify/polaris-react/pull/1686))
 - Fixed the first column of `DataTable` not rendering in iOS Safari (([#1605](https://github.com/Shopify/polaris-react/pull/1605))
+- Fixed paint loss on scroll of `TextField` `Spinner` ([#1740](https://github.com/Shopify/polaris-react/pull/1740))
 
 ### Documentation
 

src/components/TextField/TextField.scss

@@ -289,7 +289,6 @@ $stacking-order: (
   );
   border: none;
   border-left: border(dark);
-  will-change: background, box-shadow;
   transition: background duration(fast) easing(),
     box-shadow duration(fast) easing();