Bug 1780444 part 1: Use the default "overflow-clip-box" value ("padding-box") on textarea, to match other browsers on not-clipping overly-long lines at the content/padding box threshold. r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D152309

layout/style/res/forms.css

@@ -118,7 +118,6 @@ textarea {
   resize: both;
   white-space: pre-wrap;
   word-wrap: break-word;
-  overflow-clip-box: padding-box content-box;
 }
 
 /* A few properties that we don't want to inherit by default: */