[mediaqueries] Make boolean evaluation slightly more intuitive when a feature can match multiple values.

Author: tabatkins

mediaqueries/Overview.bs

@@ -513,17 +513,13 @@ Evaluating Media Features in a Boolean Context</h4>
 	like ''(color)''.
 
 	When written like this, the <a>media feature</a> is evaluated in a <dfn export>boolean context</dfn>.
-	If the feature would be true for the number ''0'',
-	a dimension with the value ''0'',
+	If the feature would be true for any value
+	<em>other than</em> the number ''0'',
+	a <a spec=css-values>dimension</a> with the value ''0'',
 	or the keyword ''none'',
-	the <a>media feature</a> evaluates to false.
-	If it would be true for any values <strong>other than</strong> the above,
-	it evaluates to true.
+	the <a>media feature</a> evaluates to true.
 	Otherwise, it evaluates to false.
 
-	Note: The “trichotomy” above allows for correct handling of MQs as false when on devices where they don't apply at all,
-	such as 'scan' on a speech device.
-
 	<div class='example'>
 		Some <a>media features</a> are designed to be written like this.
 

mediaqueries/Overview.html

@@ -803,17 +803,13 @@ <h4 class="heading settled" data-level=2.4.2 id=mq-boolean-context><span class=s
 	like <span class=css>(color)</span>.</p>
 
 <p>When written like this, the <a data-link-type=dfn href=#media-feature title="media feature">media feature</a> is evaluated in a <dfn data-dfn-type=dfn data-export="" id=boolean-context>boolean context<a class=self-link href=#boolean-context></a></dfn>.
-	If the feature would be true for the number <span class=css>0</span>,
-	a dimension with the value <span class=css>0</span>,
+	If the feature would be true for any value
+	<em>other than</em> the number <span class=css>0</span>,
+	a <a data-link-spec=css-values data-link-type=dfn href=http://www.w3.org/TR/css3-values/#dimension title=dimension>dimension</a> with the value <span class=css>0</span>,
 	or the keyword <a class=css data-link-type=maybe href=#valdef-media-update-frequency-none title=none>none</a>,
-	the <a data-link-type=dfn href=#media-feature title="media feature">media feature</a> evaluates to false.
-	If it would be true for any values <strong>other than</strong> the above,
-	it evaluates to true.
+	the <a data-link-type=dfn href=#media-feature title="media feature">media feature</a> evaluates to true.
 	Otherwise, it evaluates to false.</p>
 
-<p class=note>Note: The “trichotomy” above allows for correct handling of MQs as false when on devices where they don’t apply at all,
-	such as <a class=property data-link-type=propdesc href=#descdef-media-scan title=scan>scan</a> on a speech device.</p>
-
 	<div class=example>
 		Some <a data-link-type=dfn href=#media-feature title="media features">media features</a> are designed to be written like this.