[css-text-3] Spaces don't hang when break-spaces is specified (#2612)

[css-text-3] Spaces don't hang when break-spaces is specified

Closes #2465

Author: frivoal

css-text-3/Overview.bs

@@ -724,17 +724,20 @@ Characters and Letters</h3>
         (ignoring any intervening <a>inline box</a> boundaries)
         is removed.
       <li>If spaces or tabs at the end of a line are non-collapsible
-         but have 'white-space' set to ''pre-wrap''
-         the UA must either <a>hang</a> the <a>white space</a>
-         or visually collapse the character advance widths
-         of any overflowing spaces
-         such that they don't take up space in the line.
-         However, if 'overflow-wrap' is set to ''break-spaces'',
-         collapsing their advance width is not allowed,
-         as this would prevent the preserved spaces from wrapping.
-
-         Note: Hanging the white space rather than collapsing it
-         allows users to see the space when selecting or editing text.
+         but have 'white-space' set to ''pre-wrap'':
+	 <ul>
+	   <li>If 'overflow-wrap' does not specify ''overflow-wrap/break-spaces''
+             the UA must either <a>hang</a> the <a>white space</a>
+             or visually collapse the character advance widths
+             of any overflowing spaces
+             such that they don't take up space in the line.
+
+             Note: Hanging the white space rather than collapsing it
+             allows users to see the space when selecting or editing text.
+	   <li>Otherwise
+	     (i.e. 'overflow-wrap' property specifies ''overflow-wrap/break-spaces''),
+             hanging or collapsing the advance width of spaces at the end of the line is not allowed.
+
     </ol>
 
     Issue: Add example of hanging white space + same example right-aligned.
@@ -1241,19 +1244,17 @@ Line Breaking Details</h3>
       No hyphenation character is inserted at the break point.
     <dt><dfn>break-spaces</dfn></dt>
     <dd>Line breaks are handled as usual,
-      except that any sequence of <a>preserved</a> white space
-      that would otherwise overflow the line and <a>hang</a> as per <a href="#white-space-phase-2">Trimming and Positioning</a>
-      must be broken after the last white space character that would fit the line,
-      or after the first white space in the sequence if none would fit.
-
-      <p class="note">This value does not guarantee that there will never be any overflow due to spaces.
-      For example, if 'overflow-wrap' is set to ''break-spaces''
-      and 'white-space' to ''pre-wrap'',
-      and there is a single <a>preserved</a> space at the end of the line,
-      and that space overflows,
-      the rules of ''break-spaces'' do not introduce any additional line break,
-      and that space does overflow and <a>hang</a>.
-      Also, if the line length is so short that even a single space does not fit,
+      except that:
+      * Any sequence of <a>preserved</a> white space always takes up space,
+        including at the end of the line.
+      * A line breaking opportunity exists after every <a>preserved</a> <a>white space</a> character,
+        including between white space characters.
+
+      As preserved spaces take up space and do not hang,
+      they affect the box's intrinsic sizes ([=min-content size=] and [=max-content size=]).
+
+      <p class="note">This value does not guarantee that there will never be any overflow due to spaces:
+      for example, if the line length is so short that even a single space does not fit,
       overflow is unavoidable.</p>
 
     </dl>