Support chrome-extension:// scheme in URLPattern.

chrome/common/extensions/docs/static/webRequest.html

 <div id="pageData-name" class="pageData">WebRequest API</div>
 
 <!-- BEGIN AUTHORED CONTENT -->
 <p id="classSummary">
 Use the <code>chrome.webRequest</code> module to intercept, block,
 or modify requests in-flight. This module is still experimental. For
 information on how to use experimental APIs, see the
 <a href="experimental.html">chrome.experimental.* APIs</a> page.
 </p>
 
@@ skipping 177 matching lines @@
 <p>Depending on the specific signal, <code>opt_extraInfoSpec</code> may contain
 further strings that indicate that specific information shall be passed to the
 extension. This is used to provide detailed information on requests data only if
 explicitly requested.</p>
 
 <p>The optional <a href="#type-RequestFilter">RequestFilter</a>
 <code>opt_filter</code> allows to limit the requests for which events are
 triggered in various dimensions:
 <dl>
   <dt>URLs</dt>
-  <dd>URL patterns like <code>*://www.google.com/foo*bar</code>.</dd>
+  <dd><a href="match_patterns.html">URL patterns</a> like
+  <code>*://www.google.com/foo*bar</code>, <code>chrome-extension://*/*</code>.

[Aaron Boodman, 2011/12/06 06:43:23]

I don't think that you should call out chrome-extension:// here since it is such
an edge case.

Instead, I think we should do a quick spruce of the match pattern docs
throughout.

In match_pattern.html, it should describe the general syntax, but not a lot of
specifics. It should describe that some parts can be allowed or not allowed
depending on the API.

In each API that uses match patterns, it should describe the specifics of what
is legal. That is where you could mention chrome-extension:// for web request.

[battre, 2011/12/06 12:51:35]

Done.

+  </dd>
   <dt>Types</dt>
   <dd>Request types like <code>main_frame</code> (a document that is loaded for
   a top-level frame), <code>sub_frame</code> (a document that is loaded for an
   embedded frame), <code>image</code> (an image on a web site) and others. See
   <a href="#type-RequestFilter">RequestFilter</a>.</dd>
   <dt>Tab IDs</dt>
   <dd>The ID that identifies a specific tab in a window.</dd>
   <dt>Window IDs</dt>
   <dd>The ID that identifies a specific window.</dd>
 </p>
@@ skipping 106 matching lines @@
     // Attention: The frameUrl can be undefined in some cases. Requests may not
     // originate from a frame (e.g. requests from extensions or shared workers).
   });
 
 chrome.windows.onRemoved.addListener(
   function(windowId) {delete frameUrl[windowId];}
   );
 </pre>
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