[css-font-loading-3][editorial] Reference WebIDL BufferSource

Rather than defining a custom BinaryData typedef, the FontSource
interface should just use the BufferSource definition from WebIDL.

https://webidl.spec.whatwg.org/#BufferSource

css-font-loading-3/Overview.bs

@@ -77,11 +77,9 @@ The <code>FontFace</code> Interface</h2>
 
  The {{FontFace}} interface represents a single usable font face.
  CSS ''@font-face'' rules implicitly define FontFace objects,
- or they can be constructed manually from a url or binary data.
+ or they can be constructed manually from a url or a buffer source.
 
  <xmp class="idl">
- typedef (ArrayBuffer or ArrayBufferView) BinaryData;
-
  dictionary FontFaceDescriptors {
  CSSOMString style = "normal";
  CSSOMString weight = "normal";
@@ -99,7 +97,7 @@ The <code>FontFace</code> Interface</h2>
 
  [Exposed=(Window,Worker)]
  interface FontFace {
- constructor(CSSOMString family, (CSSOMString or BinaryData) source,
+ constructor(CSSOMString family, (CSSOMString or BufferSource) source,
  optional FontFaceDescriptors descriptors = {});
  attribute CSSOMString family;
  attribute CSSOMString style;
@@ -210,7 +208,7 @@ The Constructor</h3>
 
  A {{FontFace}} can be constructed either
  from a URL pointing to a font face file,
- or from an {{ArrayBuffer}} (or {{ArrayBufferView}}) containing the binary representation of a font face.
+ or from a {{BufferSource}} containing the binary representation of a font face.
 
  When the <dfn constructor for=FontFace>FontFace(family, source, descriptors)</dfn> method is called,
  execute these steps:
@@ -255,7 +253,7 @@ The Constructor</h3>
  2. If the {{source!!argument}} argument was a {{CSSOMString}},
  set <var>font face's</var> internal {{[[Urls]]}} slot to the string.
 
- If the {{source}} argument was a {{BinaryData}},
+ If the {{source}} argument was a {{BufferSource}},
  set <var>font face's</var> internal {{[[Data]]}} slot to the passed argument.
 
  3. If <var>font face's</var> {{[[Data]]}} slot is not <code>null</code>,
@@ -317,7 +315,7 @@ The <code>load()</code> method</h3>
 
  The {{FontFace/load()}} method of {{FontFace}}
  forces a url-based font face to request its font data and load.
- For fonts constructed from binary data,
+ For fonts constructed from a buffer source,
  or fonts that are already loading or loaded,
  it does nothing.