[fonts-4] Fix fatal errors. Sidestep error in grammar def, because I'll replace it in a bit.

Author: tabatkins

css-fonts-4/Overview.bs

@@ -810,7 +810,7 @@ This property allows authors to specify an <a>aspect value</a> for an element th
 will effectively preserve the x-height of the first choice font, whether it is substituted
 or not. Values have the following meanings:
 
-<dl>
+<dl dfn-type=value dfn-for=font-size-adjust>
 	<dt><dfn id="font-size-adjust-none-value">none</dfn>
 	<dd>
 		Do not preserve the font's x-height.
@@ -1310,7 +1310,7 @@ the ability to disable downloadable font resources, <code>@font-face</code> rule
 simply be ignored; the behavior of individual descriptors as defined in this
 specification should not be altered.
 
-<h3 id="font-family-desc">Font family: the <a href="#descdef-font-family">font-family</a> descriptor</h3>
+<h3 id="font-family-desc">Font family: the '@font-face/font-family' descriptor</h3>
 
 <pre class='descdef mq'>
 Name: font-family
@@ -2428,7 +2428,7 @@ Animatable: no
 
 Typographically, text rendered at different sizes often benefits from slightly different visual representations. For example, to aid reading at small text sizes, strokes is often thicker with larger serifs. Larger text often has a more delicate figure with more contrast between thicker and thinner strokes.
 
-<dl>
+<dl dfn-type=value dfn-for=font-optical-sizing>
 	<dt><dfn id="font-optical-sizing-auto-value">auto</dfn>
 	<dd>
 		The user agent may modify the shape of glyphs based on the font-size and the pixel density of the screen. For OpenType and TrueType fonts using font variations, this is often done by using the "opsz" font variation.
@@ -2577,7 +2577,7 @@ The '@font-palette-values' rule consists of the '@font-palette-values' at-keywor
   : <a>FONT_PALETTE_VALUES_SYM</a> <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>* '{' <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>* <a>descriptor_declaration</a>? [ ';' <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>* <a>descriptor_declaration</a>? ]* '}' <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>*
   ;
 
-<dfn>descriptor_declaration</dfn>
+<dfn>descriptor_declaration2</dfn>
   : <a href="https://www.w3.org/TR/CSS21/grammar.html#grammar"><a>property</a></a> ':' <a href="https://www.w3.org/TR/CSS21/grammar.html#scanner"><a>S</a></a>* <a href="https://www.w3.org/TR/CSS21/grammar.html#grammar"><a>expr</a></a>
   ;
 </pre>