[EME] Change how playback is resumed in loadSession() and update().
The Update Usable Key IDs algorithm now runs the
Attempt to Resume Playback If Necessary algorithm if appropriate.
--- a/encrypted-media/encrypted-media.html Thu May 22 16:03:17 2014 -0700
+++ b/encrypted-media/encrypted-media.html Thu May 22 16:17:55 2014 -0700
@@ -575,10 +575,7 @@
</ol>
</li>
<li><p>If any of the preceding steps failed, reject <var>promise</var> with a new <code><a href="http://www.w3.org/TR/dom/#exception-domexception">DOMException</a></code> whose name is the appropriate <a href="#mediakeyerror-names">error name</a> and that has an appropriate message.</p></li>
- <li>
- <p>Run the <a href="#algorithms-resume-playback">Attempt to Resume Playback If Necessary</a> algorithm on the media element.</p>
- <p>The user agent may choose to skip this step if it knows resuming will fail <span class="non-normative">(i.e. no usable key was added)</span>.</p>
- </li>
+ <li><p>If the <var title="true">session</var>'s <code><a href="#dom-usablekeyids">usableKeyIds</a></code> attribute is not empty, run the <a href="#algorithms-resume-playback">Attempt to Resume Playback If Necessary</a> algorithm on each of the associated <a href="#media-element">media element(s)</a>.</p></li>
<li><p>If <var title="true">request</var> is not null, run the <a href="#algorithms-queue-message">Queue a "message" Event</a> algorithm on the <var title="true">session</var>, providing <var title="true">request</var> and <var title="true">destination URL</var>.</p></li>
<li><p>Resolve <var>promise</var> with <var title="true">session</var>.</p></li>
</ol>
@@ -773,10 +770,6 @@
</ol>
</li>
<li><p>If any of the preceding steps failed, reject <var>promise</var> with a new <code><a href="http://www.w3.org/TR/dom/#exception-domexception">DOMException</a></code> whose name is the appropriate <a href="#mediakeyerror-names">error name</a> and that has an appropriate message.</p></li>
- <li>
- <p>Run the <a href="#algorithms-resume-playback">Attempt to Resume Playback If Necessary</a> algorithm on the media element.</p>
- <p>The user agent may choose to skip this step if it knows resuming will fail <span class="non-normative">(i.e. no usable key was added)</span>.</p>
- </li>
<li><p>If <var title="true">request</var> is not null, run the <a href="#algorithms-queue-message">Queue a "message" Event</a> algorithm on the <var title="true">session</var>, providing <var title="true">request</var> and <var title="true">destination URL</var>.</p></li>
<li><p>Resolve <var>promise</var> with <code>undefined</code>.</p></li>
</ol>
@@ -1259,9 +1252,11 @@
<p>The following steps are run:</p>
<ol>
<li><p>Let the <var title="true">session</var> be the associated <code><a href="#dom-mediakeysession">MediaKeySession</a></code> object.</p></li>
+ <li><p>Let <var title="true">previous key ids</var> be a copy of the the <var title="true">session</var>'s <code><a href="#dom-usablekeyids">usableKeyIds</a></code> attribute.</p></li>
<li><p>Let <var title="true">usable key ids</var> be an Array containing the set of key IDs for which the session contains a key the CDM <em>knows</em> is currently usable.</p></li>
<li><p>Set the <var title="true">session</var>'s <code><a href="#dom-usablekeyids">usableKeyIds</a></code> attribute to <var title="true">usable key ids</var>.</p></li>
<li><p><a href="http://www.w3.org/TR/html5/webappapis.html#queue-a-task">Queue a task</a> to <a href="http://www.w3.org/TR/html5/webappapis.html#fire-a-simple-event">fire a simple event</a> named <code><a href="#dom-eventkeyschange">keyschange</a></code> at the <var title="true">session</var>.</p></li>
+ <li><p>If <var title="true">usable key ids</var> contains values not in <var title="true">previous key ids</var>, run the <a href="#algorithms-resume-playback">Attempt to Resume Playback If Necessary</a> algorithm on each of the associated <a href="#media-element">media element(s)</a>.</p></li>
</ol>
<h3 id="algorithms-update-expiration">4.6. Update Expiration</h3>
--- a/encrypted-media/encrypted-media.xml Thu May 22 16:03:17 2014 -0700
+++ b/encrypted-media/encrypted-media.xml Thu May 22 16:17:55 2014 -0700
@@ -549,10 +549,7 @@
</ol>
</li>
<li><p>If any of the preceding steps failed, reject <var>promise</var> with a new <code><dom4ref name="exception-domexception">DOMException</dom4ref></code> whose name is the appropriate <a href="#mediakeyerror-names">error name</a> and that has an appropriate message.</p></li>
- <li>
- <p>Run the <a href="#algorithms-resume-playback">Attempt to Resume Playback If Necessary</a> algorithm on the media element.</p>
- <p>The user agent may choose to skip this step if it knows resuming will fail <span class="non-normative">(i.e. no usable key was added)</span>.</p>
- </li>
+ <li><p>If the <var title="true">session</var>'s <coderef>usableKeyIds</coderef> attribute is not empty, run the <a href="#algorithms-resume-playback">Attempt to Resume Playback If Necessary</a> algorithm on each of the associated <a href="#media-element">media element(s)</a>.</p></li>
<li><p>If <var title="true">request</var> is not null, run the <a href="#algorithms-queue-message">Queue a "message" Event</a> algorithm on the <var title="true">session</var>, providing <var title="true">request</var> and <var title="true">destination URL</var>.</p></li>
<li><p>Resolve <var>promise</var> with <var title="true">session</var>.</p></li>
</ol>
@@ -727,10 +724,6 @@
</ol>
</li>
<li><p>If any of the preceding steps failed, reject <var>promise</var> with a new <code><dom4ref name="exception-domexception">DOMException</dom4ref></code> whose name is the appropriate <a href="#mediakeyerror-names">error name</a> and that has an appropriate message.</p></li>
- <li>
- <p>Run the <a href="#algorithms-resume-playback">Attempt to Resume Playback If Necessary</a> algorithm on the media element.</p>
- <p>The user agent may choose to skip this step if it knows resuming will fail <span class="non-normative">(i.e. no usable key was added)</span>.</p>
- </li>
<li><p>If <var title="true">request</var> is not null, run the <a href="#algorithms-queue-message">Queue a "message" Event</a> algorithm on the <var title="true">session</var>, providing <var title="true">request</var> and <var title="true">destination URL</var>.</p></li>
<li><p>Resolve <var>promise</var> with <code>undefined</code>.</p></li>
</ol>
@@ -1185,9 +1178,11 @@
<p>The following steps are run:</p>
<ol>
<li><p>Let the <var title="true">session</var> be the associated <coderef>MediaKeySession</coderef> object.</p></li>
+ <li><p>Let <var title="true">previous key ids</var> be a copy of the the <var title="true">session</var>'s <coderef>usableKeyIds</coderef> attribute.</p></li>
<li><p>Let <var title="true">usable key ids</var> be an Array containing the set of key IDs for which the session contains a key the CDM <em>knows</em> is currently usable.</p></li>
<li><p>Set the <var title="true">session</var>'s <coderef>usableKeyIds</coderef> attribute to <var title="true">usable key ids</var>.</p></li>
<li><p><Queue-a-task/> to <fire-a-simple-event/> named <coderef prefix="event">keyschange</coderef> at the <var title="true">session</var>.</p></li>
+ <li><p>If <var title="true">usable key ids</var> contains values not in <var title="true">previous key ids</var>, run the <a href="#algorithms-resume-playback">Attempt to Resume Playback If Necessary</a> algorithm on each of the associated <a href="#media-element">media element(s)</a>.</p></li>
</ol>
<h3 id="algorithms-update-expiration">4.6. Update Expiration</h3>