[css-values-3] Remove consideration of scrollbars in viewport unit computation due to lack of implementations. <https://lists.w3.org/Archives/Public/www-style/2017Sep/0014.html> Fixes w3c#1766

Author: fantasai

css-values-3/Overview.bs

@@ -1006,9 +1006,7 @@ Viewport-percentage lengths: the ''vw'', ''vh'', ''vmin'', ''vmax'' units</h4>
 	<a href="https://www.w3.org/TR/CSS21/visudet.html#containing-block-details">initial containing block</a>.
 	When the height or width of the initial containing block is changed,
 	they are scaled accordingly.
-	However, when the value of 'overflow' on the root element is ''overflow/auto'',
-	any scroll bars are assumed not to exist.
-	<span class='note'>Note that the initial containing block's size is affected by the presence of scrollbars on the viewport.</span>
+	However, any scrollbars are assumed not to exist.
 
 	For paged media, the exact definition of the viewport-percentage lengths
 	is deferred to [[!CSS3PAGE]].
@@ -2127,12 +2125,16 @@ Changes</h2>
 	Changes since the <a href="https://www.w3.org/TR/2016/CR-css-values-3-20160929/">29 September 2016 Candidate Recommendation</a> are:
 
 	<ul>
+		<li>Removed <a href="#change-2012-vwh-scrollbars">consideration of scrollbars</a>
+			in computing viewport units due to lack of implementations.
+			(<a href="https://drafts.csswg.org/css-values-3/issues-cr-2016#issue-15">Issue 15</a>)
 		<li>Inlined the <<position>> definition and dropped the three-value syntaxes
 			to allow for unambiguous combination in complex grammars.
 			This effectively removes that syntax from 'object-position',
 			but allows <<position>> to be re-used e.g. in [[CSS-TRANSFORMS-1]] for 3D positions.
 			(See <a href="https://lists.w3.org/Archives/Public/www-style/2017Feb/0052.html">discussion</a>.)
-		<li>Reverted previous change to allow zero angles to drop their unit; this will instead be special-cased where needed for backwards-compatibility.
+		<li>Reverted previous change to allow zero angles to drop their unit;
+			this will instead be special-cased where needed for backwards-compatibility.
 			(See <a href="https://lists.w3.org/Archives/Public/www-style/2017Apr/0027.html">discussion</a>)
 		<li>Fixed grammar error that disallowed numeric expressions as denominators in ''calc()''.
 			(<a href="https://drafts.csswg.org/css-values-3/issues-cr-2016#issue-12">Issue 12</a>)
@@ -2192,7 +2194,8 @@ Changes</h2>
 	<ul>
 		<li>Corrected <code>wqname</code> in the ''attr()'' syntax to <code>qname</code>
 		<li>Made undefined namespace prefixes in ''attr()'' invalidate the function.
-		<li>Per <a href="http://lists.w3.org/Archives/Public/www-style/2013Jan/0616.html">WG resolution</a>,
+		<li id="change-2012-vwh-scrollbars">
+			Per <a href="http://lists.w3.org/Archives/Public/www-style/2013Jan/0616.html">WG resolution</a>,
 			made <a href="#viewport-relative-lengths">viewport-percentage units</a> respect scrollbars on the viewport
 			unless 'overflow' is ''overflow/auto'' (in which case they ignore the presence of scrollbars).
 		<li>Deferred exact definition of <a href="#viewport-relative-lengths">viewport-percentage units</a>

css-values-3/issues-cr-2016.bsi

@@ -115,3 +115,10 @@ Comment:  https://lists.w3.org/Archives/Public/www-style/2017Apr/0027.html
 Closed:   Accepted
 Resolved: https://lists.w3.org/Archives/Public/www-style/2017Apr/0027.html
 ----
+Issue 15.
+Summary:  Consideration of scrollbars in viewport unit computation not implemented
+From:     David Baron
+Comment:  https://github.com/w3c/csswg-drafts/issues/1766
+Closed:   Accepted
+Resolved: https://lists.w3.org/Archives/Public/www-style/2017Sep/0014.html
+----

css-values-3/issues-cr-2016.html

@@ -149,6 +149,13 @@ <h1>CSS Values and Units Level 3 Disposition of Comments for 2016-09-29 CR</h1>
 <span>Comment:  <a href='https://lists.w3.org/Archives/Public/www-style/2017Apr/0027.html'>https://lists.w3.org/Archives/Public/www-style/2017Apr/0027.html</a> <a href="https://www.w3.org/Mail/flatten/index?subject=https%3A%2F%2Flists.w3.org%2FArchives%2FPublic%2Fwww-style/2017Apr/0027.html"><abbr title="Thread">&#x2208;</abbr></a></span>
 <span class="a">Closed:   Accepted</span>
 <span>Resolved: <a href='https://lists.w3.org/Archives/Public/www-style/2017Apr/0027.html'>https://lists.w3.org/Archives/Public/www-style/2017Apr/0027.html</a> <a href="https://www.w3.org/Mail/flatten/index?subject=https%3A%2F%2Flists.w3.org%2FArchives%2FPublic%2Fwww-style/2017Apr/0027.html"><abbr title="Thread">&#x2208;</abbr></a></span></pre>
+<pre class=' a' id='issue-15'>
+<span>Issue 15. <a href='#issue-15'>#</a></span>
+<span>Summary:  Consideration of scrollbars in viewport unit computation not implemented</span>
+<span>From:     David Baron</span>
+<span>Comment:  <a href='https://github.com/w3c/csswg-drafts/issues/1766'>https://github.com/w3c/csswg-drafts/issues/1766</a></span>
+<span class="a">Closed:   Accepted</span>
+<span>Resolved: <a href='https://lists.w3.org/Archives/Public/www-style/2017Sep/0014.html'>https://lists.w3.org/Archives/Public/www-style/2017Sep/0014.html</a> <a href="https://www.w3.org/Mail/flatten/index?subject=https%3A%2F%2Flists.w3.org%2FArchives%2FPublic%2Fwww-style/2017Sep/0014.html"><abbr title="Thread">&#x2208;</abbr></a></span></pre>
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