[css-ui-3] Excplitely leave coordinate systems undefined

Author: frivoal

css-ui/Overview.bs

@@ -1040,6 +1040,10 @@ The x-coordinate and y-coordinate of the position
 in the cursor's coordinate system (left/top relative)
 which represents the precise position that is being pointed to.
 
+Note: This specification does not define
+how the coordinate systems of the various types of <<image>> are established,
+and defers these definitions to [[!CSS4-IMAGES]].
+
 If the values are unspecified,
 then the intrinsic hotspot defined inside the image resource itself is used.
 If both the values are unspecific and the referenced cursor has no defined hotspot,

css-ui/Overview.html

@@ -2289,6 +2289,11 @@ <h4 class="heading settled" data-level="6.1.1" id="cursor"><span class="secno">6
 which represents the precise position that is being pointed to.
 
 
+     <p class="note" role="note">Note: This specification does not define
+how the coordinate systems of the various types of <a class="production css" data-link-type="type" href="http://dev.w3.org/csswg/css-images-3/#typedef-image" title="Expands to: ">&lt;image></a> are established,
+and defers these definitions to <a data-link-type="biblio" href="#biblio-css4-images">[CSS4-IMAGES]</a>.</p>
+
+
      <p>If the values are unspecified,
 then the intrinsic hotspot defined inside the image resource itself is used.
 If both the values are unspecific and the referenced cursor has no defined hotspot,
@@ -3892,6 +3897,8 @@ <h3 class="no-num heading settled" id="normative"><span class="content">Normativ
    <dd>CSS Values and Units Module Level 3 URL: <a href="http://www.w3.org/TR/css3-values/">http://www.w3.org/TR/css3-values/</a>
    <dt id="biblio-css-writing-modes-3"><a class="self-link" href="#biblio-css-writing-modes-3"></a>[CSS-WRITING-MODES-3]
    <dd>Elika Etemad; Koji Ishii. <a href="http://www.w3.org/TR/css-writing-modes-3/">CSS Writing Modes Level 3</a>. 20 March 2014. CR. URL: <a href="http://www.w3.org/TR/css-writing-modes-3/">http://www.w3.org/TR/css-writing-modes-3/</a>
+   <dt id="biblio-css4-images"><a class="self-link" href="#biblio-css4-images"></a>[CSS4-IMAGES]
+   <dd>Elika Etemad; Tab Atkins Jr.. <a href="http://www.w3.org/TR/css4-images/">CSS Image Values and Replaced Content Module Level 4</a>. 11 September 2012. WD. URL: <a href="http://www.w3.org/TR/css4-images/">http://www.w3.org/TR/css4-images/</a>
    <dt id="biblio-cssom-1"><a class="self-link" href="#biblio-cssom-1"></a>[CSSOM-1]
    <dd>CSS Object Model Level 1 URL: <a href="http://www.w3.org/TR/cssom/">http://www.w3.org/TR/cssom/</a>
    <dt id="biblio-rfc2119"><a class="self-link" href="#biblio-rfc2119"></a>[RFC2119]