[e] (0) Define 'empty'.

Fixing http://www.w3.org/Bugs/Public/show_bug.cgi?id=10604

git-svn-id: http://svn.whatwg.org/webapps@5524 340c8d12-0b0e-0410-8428-c7bf67bfef74

complete.html

@@ -2733,6 +2733,10 @@ <h4 id=dom-trees><span class=secno>2.1.3 </span>DOM trees</h4>
   only if its new value is different than its previous value; setting
   an attribute to a value it already has does not change it.</p>
 
+  <p>The term <dfn title="">empty</dfn>, when used of an attribute
+  value, text node, or string, means that the length of the text is
+  zero (i.e. not even containing spaces or control characters).</p>
+
 
   <h4 id=scripting-0><span class=secno>2.1.4 </span>Scripting</h4>
 

index

@@ -2710,6 +2710,10 @@ a.setAttribute('href', 'http://example.com/'); // change the content attribute d
   only if its new value is different than its previous value; setting
   an attribute to a value it already has does not change it.</p>
 
+  <p>The term <dfn title="">empty</dfn>, when used of an attribute
+  value, text node, or string, means that the length of the text is
+  zero (i.e. not even containing spaces or control characters).</p>
+
 
   <h4 id=scripting-0><span class=secno>2.1.4 </span>Scripting</h4>
 

source

@@ -1646,6 +1646,10 @@ a.setAttribute('href', 'http://example.com/'); // change the content attribute d
   only if its new value is different than its previous value; setting
   an attribute to a value it already has does not change it.</p>
 
+  <p>The term <dfn title="">empty</dfn>, when used of an attribute
+  value, text node, or string, means that the length of the text is
+  zero (i.e. not even containing spaces or control characters).</p>
+
 
   <h4>Scripting</h4>