Fix performance issues with NNTP....

chrome/browser/resources/new_new_tab.css

 html {
   /* This is needed because of chrome://theme/css/new_tab.css */
   height: 100%;
 }
 
 body {
   margin: 0;
 }
 
 #main {
@@ skipping 522 matching lines @@
 #lower-sections {
   position: relative;
   overflow: hidden;
   -webkit-transition: height .5s, width .5s, opacity .5s;
   white-space: nowrap;
 }
 
 #lower-sections .section {
   -webkit-transition: width .5s, opacity .5s, left .5s;
   -webkit-box-sizing: border-box;
+  width: 460px; /* Set default size so we don't have to do a js layout at
+                   load */
+}
+
+.small #lower-sections .section {
+  width: 336px; /* Same here, see above */
 }
 
 #lower-sections .spacer {
   width: 20px;
   -webkit-transition: width .5s;
   display: inline-block;
 }
 
-.loading * {
-  -webkit-transition: none;
-}
-
 #thumb-checkbox {
   background-image: url(chrome://theme/newtab_thumb_off);
 }
 
 #thumb-checkbox:hover {
   background-image: url(chrome://theme/newtab_thumb_off_h);
 }
 
 #thumb-checkbox:active {
   background-image: url(chrome://theme/newtab_thumb_off_p);
@@ skipping 68 matching lines @@
 #option-menu > div {
   padding: 3px 8px;
   overflow: hidden;
   text-overflow: ellipsis;
 }
 
 #option-menu > [selected] {
   background-color: hsla(213, 66%, 57%, 1);
   color: white;
 }