Add support for experiments

This change refactors the options logic and adds support for
experiments: a new type of options which are not shown in the options
page (their usage will be similar to Chrome flags).

Experiments can be set from the
chrome-extension://{extension_id}/options/experiments.html page.

This code refactoring simplifies the options definition. Each option now
has a default value, and a context: the place where the option is set
(options, experiments, internal, deprecated).

Change-Id: I358ae07c832acae6b4536788c4dbe12a0e4730bf
diff --git a/src/options/options.html b/src/options/options.html
index 69cddd8..8dc8129 100644
--- a/src/options/options.html
+++ b/src/options/options.html
@@ -8,41 +8,44 @@
     <link rel="stylesheet" href="chrome_style/chrome_style.css">
   </head>
   <body>
-    <a href="https://gerrit.avm99963.com/plugins/gitiles/infinitegforums/+/master/docs/features.md" target="_blank" class="features-link">
-      <!--
-        Material Design Icon - action/help_outline
-         - LICENSE: Apache License Version 2.0
-         - Source: https://github.com/google/material-design-icons/
-         - Author: Google LLC
-      -->
-      <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M0 0h24v24H0V0z" fill="none"/><path d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm0 18c-4.41 0-8-3.59-8-8s3.59-8 8-8 8 3.59 8 8-3.59 8-8 8zm-1-4h2v2h-2zm1.61-9.96c-2.06-.3-3.88.97-4.43 2.79-.18.58.26 1.17.87 1.17h.2c.41 0 .74-.29.88-.67.32-.89 1.27-1.5 2.3-1.28.95.2 1.65 1.13 1.57 2.1-.1 1.34-1.62 1.63-2.45 2.88 0 .01-.01.01-.01.02-.01.02-.02.03-.03.05-.09.15-.18.32-.25.5-.01.03-.03.05-.04.08-.01.02-.01.04-.02.07-.12.34-.2.75-.2 1.25h2c0-.42.11-.77.28-1.07.02-.03.03-.06.05-.09.08-.14.18-.27.28-.39.01-.01.02-.03.03-.04.1-.12.21-.23.33-.34.96-.91 2.26-1.65 1.99-3.56-.24-1.74-1.61-3.21-3.35-3.47z"/></svg>
-    </a>
-    <form>
-      <div class="option"><input type="checkbox" id="list"> <label for="list" data-i18n="list"></label></div>
-      <div class="option"><input type="checkbox" id="thread"> <label for="thread" data-i18n="thread"></label></div>
-      <div class="option"><input type="checkbox" id="threadall"> <label for="threadall" data-i18n="threadall"></label></div>
-      <h4 data-i18n="enhancements"></h4>
-      <div class="option"><input type="checkbox" id="fixedtoolbar"> <label for="fixedtoolbar" data-i18n="fixedtoolbar"></label></div>
-      <div class="option"><input type="checkbox" id="redirect"> <label for="redirect" data-i18n="redirect"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
-      <div class="option"><input type="checkbox" id="history"> <label for="history" data-i18n="history"></label></div>
-      <div class="option"><input type="checkbox" id="loaddrafts"> <label for="loaddrafts" data-i18n="loaddrafts"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
-      <div class="option"><input type="checkbox" id="increasecontrast"> <label for="increasecontrast" data-i18n="increasecontrast"></label></div>
-      <div class="option"><input type="checkbox" id="stickysidebarheaders"> <label for="stickysidebarheaders" data-i18n="stickysidebarheaders"></label></div>
-      <div class="option"><input type="checkbox" id="ccdarktheme"> <label for="ccdarktheme" data-i18n="ccdarktheme"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
-      <div class="option"><input type="checkbox" id="ccforcehidedrawer"> <label for="ccforcehidedrawer" data-i18n="ccforcehidedrawer"></label></div>
-      <div id="dragndrop-wrapper" class="option" hidden><input type="checkbox" id="ccdragndropfix"> <label for="ccdragndropfix" data-i18n="ccdragndropfix"></label></div>
-      <div class="option"><input type="checkbox" id="batchlock"> <label for="batchlock" data-i18n="batchlock"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
-      <div class="option"><input type="checkbox" id="smei_sortdirection"> <label for="smei_sortdirection" data-i18n="smei_sortdirection"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
-      <div class="option"><input type="checkbox" id="enhancedannouncementsdot"> <label for="enhancedannouncementsdot" data-i18n="enhancedannouncementsdot"></label></div>
-      <div class="option"><input type="checkbox" id="repositionexpandthread"> <label for="repositionexpandthread" data-i18n="repositionexpandthread"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
-      <h4 data-i18n="profileindicator_header"></h4>
-      <div class="option"><input type="checkbox" id="profileindicator"> <label for="profileindicator" data-i18n="profileindicator"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
-      <div class="option"><input type="checkbox" id="profileindicatoralt"> <label for="profileindicatoralt" data-i18n="profileindicatoralt"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
-      <div class="option"><a href="https://gerrit.avm99963.com/plugins/gitiles/infinitegforums/+/refs/heads/master/docs/op_indicator.md" target="_blank" rel="noreferrer noopener" data-i18n="profileindicator_moreinfo"></a></div>
-      <div class="actions"><button id="save" data-i18n="save"></button></div>
-    </form>
-    <div id="save-indicator"></div>
+    <main>
+      <a href="https://gerrit.avm99963.com/plugins/gitiles/infinitegforums/+/master/docs/features.md" target="_blank" class="features-link">
+        <!--
+          Material Design Icon - action/help_outline
+           - LICENSE: Apache License Version 2.0
+           - Source: https://github.com/google/material-design-icons/
+           - Author: Google LLC
+        -->
+        <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M0 0h24v24H0V0z" fill="none"/><path d="M12 2C6.48 2 2 6.48 2 12s4.48 10 10 10 10-4.48 10-10S17.52 2 12 2zm0 18c-4.41 0-8-3.59-8-8s3.59-8 8-8 8 3.59 8 8-3.59 8-8 8zm-1-4h2v2h-2zm1.61-9.96c-2.06-.3-3.88.97-4.43 2.79-.18.58.26 1.17.87 1.17h.2c.41 0 .74-.29.88-.67.32-.89 1.27-1.5 2.3-1.28.95.2 1.65 1.13 1.57 2.1-.1 1.34-1.62 1.63-2.45 2.88 0 .01-.01.01-.01.02-.01.02-.02.03-.03.05-.09.15-.18.32-.25.5-.01.03-.03.05-.04.08-.01.02-.01.04-.02.07-.12.34-.2.75-.2 1.25h2c0-.42.11-.77.28-1.07.02-.03.03-.06.05-.09.08-.14.18-.27.28-.39.01-.01.02-.03.03-.04.1-.12.21-.23.33-.34.96-.91 2.26-1.65 1.99-3.56-.24-1.74-1.61-3.21-3.35-3.47z"/></svg>
+      </a>
+      <form>
+        <div class="option"><input type="checkbox" id="list"> <label for="list" data-i18n="list"></label></div>
+        <div class="option"><input type="checkbox" id="thread"> <label for="thread" data-i18n="thread"></label></div>
+        <div class="option"><input type="checkbox" id="threadall"> <label for="threadall" data-i18n="threadall"></label></div>
+        <h4 data-i18n="enhancements"></h4>
+        <div class="option"><input type="checkbox" id="fixedtoolbar"> <label for="fixedtoolbar" data-i18n="fixedtoolbar"></label></div>
+        <div class="option"><input type="checkbox" id="redirect"> <label for="redirect" data-i18n="redirect"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
+        <div class="option"><input type="checkbox" id="history"> <label for="history" data-i18n="history"></label></div>
+        <div class="option"><input type="checkbox" id="loaddrafts"> <label for="loaddrafts" data-i18n="loaddrafts"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
+        <div class="option"><input type="checkbox" id="increasecontrast"> <label for="increasecontrast" data-i18n="increasecontrast"></label></div>
+        <div class="option"><input type="checkbox" id="stickysidebarheaders"> <label for="stickysidebarheaders" data-i18n="stickysidebarheaders"></label></div>
+        <div class="option"><input type="checkbox" id="ccdarktheme"> <label for="ccdarktheme" data-i18n="ccdarktheme"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
+        <div class="option"><input type="checkbox" id="ccforcehidedrawer"> <label for="ccforcehidedrawer" data-i18n="ccforcehidedrawer"></label></div>
+        <div id="dragndrop-wrapper" class="option" hidden><input type="checkbox" id="ccdragndropfix"> <label for="ccdragndropfix" data-i18n="ccdragndropfix"></label></div>
+        <div class="option"><input type="checkbox" id="batchlock"> <label for="batchlock" data-i18n="batchlock"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
+        <div class="option"><input type="checkbox" id="smei_sortdirection"> <label for="smei_sortdirection" data-i18n="smei_sortdirection"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
+        <div class="option"><input type="checkbox" id="enhancedannouncementsdot"> <label for="enhancedannouncementsdot" data-i18n="enhancedannouncementsdot"></label></div>
+        <div class="option"><input type="checkbox" id="repositionexpandthread"> <label for="repositionexpandthread" data-i18n="repositionexpandthread"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
+        <h4 data-i18n="profileindicator_header"></h4>
+        <div class="option"><input type="checkbox" id="profileindicator"> <label for="profileindicator" data-i18n="profileindicator"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
+        <div class="option"><input type="checkbox" id="profileindicatoralt"> <label for="profileindicatoralt" data-i18n="profileindicatoralt"></label> <span class="experimental-label" data-i18n="experimental_label"></span></div>
+        <div class="option"><a href="https://gerrit.avm99963.com/plugins/gitiles/infinitegforums/+/refs/heads/master/docs/op_indicator.md" target="_blank" rel="noreferrer noopener" data-i18n="profileindicator_moreinfo"></a></div>
+        <div class="actions"><button id="save" data-i18n="save"></button></div>
+      </form>
+      <div id="save-indicator"></div>
+    </main>
     <script src="../common/common.js"></script>
-    <script src="options.js"></script>
+    <script src="options_bit.js"></script>
+    <script src="options_common.js"></script>
   </body>
 </html>