[css-images] Add issue about elementSources and using ID selectors.

--HG--
extra : rebase_source : 536f8ecf33ee75ca5a4faf085aae4c2991aab4ee

Author: tabatkins

css-images/Overview.html

@@ -870,6 +870,15 @@ <h4 class="heading settled heading" data-level=3.4.2 id=elementsources><span cla
 			it’s then looked for in the document as normal.
 	</ul>
 
+	<p class=issue id=issue-6bc3ba98><a class=self-link href=#issue-6bc3ba98></a>
+		This reuse of the ID selector matches Moz behavior.
+		I’m trying to avoid slapping a <a class="production css-code" data-link-type=type href=http://dev.w3.org/csswg/css-values-3/#identifier-value title="<custom-ident>">&lt;custom-ident&gt;</a> right in the beginning of the grammar,
+		as that eats too much syntax-space.
+		Another possibility, though, is to start the value with a language-defined keyword
+		<em>followed by</em> a <a class="production css-code" data-link-type=type href=http://dev.w3.org/csswg/css-values-3/#identifier-value title="<custom-ident>">&lt;custom-ident&gt;</a>,
+		like <span class=css data-link-type=maybe title="element(external fancy)">element(external fancy)</span> or something.
+		Naming suggestions welcome.
+
 	<div class=example>
 		For example, fancy animating backgrounds can be done with an external canvas:
 
@@ -2968,6 +2977,15 @@ <h2 class="no-num heading settled" id=issues-index><span class=content>Issues In
 				or can we just render it as a stacking context when rendering it to element()?
 
 <a href=#issue-6fabc13d> ↵ </a></div><div class=issue>
+		This reuse of the ID selector matches Moz behavior.
+		I’m trying to avoid slapping a <a class="production css-code" data-link-type=type href=http://dev.w3.org/csswg/css-values-3/#identifier-value title="<custom-ident>">&lt;custom-ident&gt;</a> right in the beginning of the grammar,
+		as that eats too much syntax-space.
+		Another possibility, though, is to start the value with a language-defined keyword
+		<em>followed by</em> a <a class="production css-code" data-link-type=type href=http://dev.w3.org/csswg/css-values-3/#identifier-value title="<custom-ident>">&lt;custom-ident&gt;</a>,
+		like <span class=css data-link-type=maybe title="element(external fancy)">element(external fancy)</span> or something.
+		Naming suggestions welcome.
+
+	<a href=#issue-6bc3ba98> ↵ </a></div><div class=issue>
 		We should add the ability to move the focus of the gradient,
 		as in the original -webkit-gradient() function.
 		See proposal in <a href=http://lists.w3.org/Archives/Public/www-style/2011Nov/0210.html>http://lists.w3.org/Archives/Public/www-style/2011Nov/0210.html</a>

css-images/Overview.src.html

@@ -840,6 +840,15 @@ <h4 id='elementsources'>
 			it's then looked for in the document as normal.
 	</ul>
 
+	<p class='issue'>
+		This reuse of the ID selector matches Moz behavior.
+		I'm trying to avoid slapping a <<custom-ident>> right in the beginning of the grammar,
+		as that eats too much syntax-space.
+		Another possibility, though, is to start the value with a language-defined keyword
+		<em>followed by</em> a <<custom-ident>>,
+		like ''element(external fancy)'' or something.
+		Naming suggestions welcome.
+
 	<div class='example'>
 		For example, fancy animating backgrounds can be done with an external canvas: