[css-text-3] Require hanging, allow visual collapsing *in addition*, otherwise browsers will be inconsistent in how they center/end-align text (which is not OK) not just in how they handle overflowing spaces (which is OK)

Author: fantasai

css-text-3/Overview.bs

@@ -766,10 +766,9 @@ Characters and Letters</h3>
         at the end of a line:
         <ul>
           <li>If 'white-space' is set to ''pre-wrap'',
-             the UA must either <a>hang</a> this sequence
-             or visually collapse the character advance widths
-             of any that overflow
-             such that they don't take up space in the line.
+             the UA must <a>hang</a> this sequence.
+             It may also visually collapse the character advance widths
+             of any that would otherwise overflow.
 
              Note: Hanging the white space rather than collapsing it
              allows users to see the space when selecting or editing text.