Issue 4136 - Support Chrome's dark devtools theme

skin/devtools-panel.css

 *
 {
   font-family: 'Lucida Grande', 'Segoe UI', Ubuntu, Tahoma, Arial, sans-serif;
   font-size: 11px;
   box-sizing: border-box;
 }
 
 html
 {
   height: 100%;
   overflow: hidden;
 }
 
 body
 {
   margin: 0;
   color: #303942;
   display: flex;
   height: 100%;
   flex-direction: column;
+}
+
+body.default
+{
+  background-color: #ffffff;
 }
 
 body.dark
 {
   color: #ffffff;
 }
 
 table
 {
   table-layout: fixed;
@@ skipping 55 matching lines @@
 {
   line-height: 17px;
 
   /* This background image gives every other row a gray background.
    * This is simlar to "tr:nth-child(odd) background-color: #eee;".
    * However, we can't do it that way, since some rows might be hidden.
    */
   background-image: url(data:image/gif;base64,R0lGODdhAQBQAIABAO7u7v///ywAAAAAAQBQAAACC4SPqcsYD6OctMYCADs=);
   background-repeat: repeat;
 }
+
 body.dark #items table
 {
   background-image: url(data:image/gif;base64,R0lGODdhAQBQAIACACQkJExMTCwAAAAAAQBQAAACC4yPqcsID6OctMYCADs=);
 }
-
 
 #items tr
 {
   height: 40px;
 }
 
 #items tr[data-state=blocked]
 {
   color: red;
 }
@@ skipping 119 matching lines @@
 
 .filtered-by-search
 {
   display: none;
 }
 
 body.dark #reload
 {
   color: #2a67e7;
 }