Use the URL from the response, if it has one

This mostly affects the way stylesheets work in service workers. See
w3c/ServiceWorker#757 for details.

Overview.html

@@ -7,7 +7,7 @@
 
 <p><a class="logo" href="https://whatwg.org/"><img alt="WHATWG" height="100" src="https://resources.whatwg.org/logo-fetch.svg" width="100"></a>
 <h1 id="cors">Fetch</h1>
-<h2 class="no-num no-toc" id="living-standard-—-last-updated-15-october-2015">Living Standard — Last Updated 15 October 2015</h2>
+<h2 class="no-num no-toc" id="living-standard-—-last-updated-28-october-2015">Living Standard — Last Updated 28 October 2015</h2>
 
 <dl>
  <dt>Participate:
@@ -1239,7 +1239,7 @@ <h4 id="readablestream"><span class="secno">3.6.1 </span>ReadableStream</h4>
 <a href="#concept-readablestream"><code title="concept-ReadableStream">ReadableStream</code></a> object with given a byte stream
 <var>byteStream</var>, run these steps:
 
-<p class="XXX">This operation is a workaround and will be deleted when we stop using byte streams. 
+<p class="XXX">This operation is a workaround and will be deleted when we stop using byte streams.
 
 <ol>
  <li><p>Let <var>stream</var> be a <a href="#concept-readablestream"><code title="concept-ReadableStream">ReadableStream</code></a> object
@@ -1904,9 +1904,9 @@ <h3 id="main-fetch"><span class="secno">5.1 </span>Main fetch</h3>
   <p class="note">This operates on <var title="">response</var> as this algorithm is not
   supposed to observe <var>internalResponse</var>.
 
- <li><p>Set <var title="">internalResponse</var>'s
- <a href="#concept-response-url-list" title="concept-response-url-list">url list</a> to a copy of
- <var title="">request</var>'s <a href="#concept-request-url-list" title="concept-request-url-list">url list</a>.
+ <li><p>If <var>internalResponse</var>'s <a href="#concept-response-url-list" title="concept-response-url-list">url list</a> is
+ empty, set it to a copy of <var>request</var>'s
+ <a href="#concept-request-url-list" title="concept-request-url-list">url list</a>.
 
  <li>
   <p>If <var title="">request</var>'s <a href="#synchronous-flag">synchronous flag</a> is set,

Overview.src.html

@@ -1178,7 +1178,7 @@ <h4>ReadableStream</h4>
 <code title=concept-ReadableStream>ReadableStream</code> object with given a byte stream
 <var>byteStream</var>, run these steps:
 
-<p class=XXX>This operation is a workaround and will be deleted when we stop using byte streams. 
+<p class=XXX>This operation is a workaround and will be deleted when we stop using byte streams.
 
 <ol>
  <li><p>Let <var>stream</var> be a <code title=concept-ReadableStream>ReadableStream</code> object
@@ -1843,9 +1843,9 @@ <h3>Main fetch</h3>
   <p class=note>This operates on <var title>response</var> as this algorithm is not
   supposed to observe <var>internalResponse</var>.
 
- <li><p>Set <var title>internalResponse</var>'s
- <span title=concept-response-url-list>url list</span> to a copy of
- <var title>request</var>'s <span title=concept-request-url-list>url list</span>.
+ <li><p>If <var>internalResponse</var>'s <span title=concept-response-url-list>url list</span> is
+ empty, set it to a copy of <var>request</var>'s
+ <span title=concept-request-url-list>url list</span>.
 
  <li>
   <p>If <var title>request</var>'s <span>synchronous flag</span> is set,