MD Settings: Update spell check section to spec

chrome/browser/resources/settings/settings_shared_css.html

 <link rel="import" href="/settings_root_css.html">
 
 <!-- Common styles for Material Design settings. -->
 <dom-module id="settings-shared">
   <template>
     <style>
       h2 {
         align-items: center;
         display: flex;
         font-size: 100%;
@@ skipping 169 matching lines @@
         overflow: hidden;
         white-space: nowrap;
       }
 
       .list-item > .start {
         flex: 1;
         overflow: hidden;
         white-space: nowrap;
       }
 
+      .list-item > label.start {
+        align-items: center;
+        display: flex;

[dschuyler, 2016/06/10 21:49:46]

Can we move the flex: 1 here and 
remove the 
.list-item > label.start > span {

[michaelpg, 2016/06/20 19:55:37]

Done.

+      }
+
+      .list-item > label.start > span {
+        flex: 1;
+      }
+
+      .list-item > label span[disabled] {
+        opacity: .5;  /* TODO(michaelpg): check this value with bettes. */
+      }
+
       .list-item > paper-icon-item {
         padding: 0;
       }
 
       /* This button has no ink ripple. */
       .list-item.list-button {
         align-items: center;
         color: var(--google-blue-500);
         font-weight: 500;
       }
@@ skipping 74 matching lines @@
 
       .favicon-image {
         background-repeat: no-repeat;
         background-size: contain;
         height: 16px;
         width: 16px;
       }
     </style>
   </template>
 </dom-module>