Some fixes to make NNTP themes work again.

chrome/browser/resources/new_tab_theme.css

 html {
   background-image:url(chrome://theme/theme_ntp_background?$1);
   background-color:$2;
   background-position:$3;
   background-repeat:$5;
   overflow:hidden;
 }
 html[bookmarkbarattached='true'] {
   background-position:$4;
 }
 body {
   color: $8;
   height:100%;
   overflow:auto;
 }
+#main {
+  background: url(chrome://theme/product_logo?$1) no-repeat 0 8px;
+}
+:visited,
+.link {
+  cursor: pointer;
+  text-decoration: underline;
+  color: $8;
+}
 .thumbnail-container,
 .list > .thumbnail-container > .title,
 .list .title > div,
 .thumbnail-container > .title {
   color: $8;
 }
 .thumbnail-container:focus .thumbnail,
 .thumbnail-container:hover .thumbnail {
   border-color: $6;
 }
 .thumbnail-container:focus .edit-bar,
 .thumbnail-container:hover .edit-bar {
   background-color: $6;
   background-image: -webkit-gradient(linear, left top, left bottom,
                                      from($7),
                                      to($6));
 }
 .thumbnail-container:hover > .edit-mode-border {
   background-color: $6;
 }
-:visited,
-.link {
-  cursor: pointer;
-  text-decoration: underline;
-  color: $8;
-}
 .edit-mode-border {
   background-color: $7;
 }
 .section {
   border: 1px solid $7;
 }
 .section > h2 {
   background-color: $7;
   background-image: -webkit-gradient(linear, left top, left bottom,
                                      from($7),
                                      to($6));
   color: $$1;
 }
-#view-toolbar input {
+#view-toolbar > input {
   background-color: $7;
   -webkit-mask-image: url(chrome://theme/newtab_menu_mask);
 }
 #option-menu > [selected] {
   background-color: $7;
   color: white;
 }
 .tips-title {
   color: $$1;
 }