MD Settings: up contast of headers and other things that use grey 500 on white

chrome/browser/resources/settings/people_page/change_picture.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/cr_elements/icons.html">
 <link rel="import" href="chrome://resources/html/i18n_behavior.html">
 <link rel="import" href="chrome://resources/html/util.html">
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-a11y-keys/iron-a11y-keys.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-selector/iron-selector.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button.html">
 <link rel="import" href="../i18n_setup.html">
 <link rel="import" href="../icons.html">
@@ skipping 44 matching lines @@
       #availableIcons img.iron-selected {
         padding: 0;
       }
 
       #availableIcons iron-icon.iron-selected {
         padding: 16px;
       }
 
       #authorCredit,
       #authorCredit a {
-        color: var(--paper-grey-500);
+        color: var(--paper-grey-600);
       }
 
       #previewPane {
         -webkit-margin-end: 10px;
         flex-shrink: 0;
         width: 228px;
       }
 
       #previewPane img {
         display: block;
@@ skipping 66 matching lines @@
         </div>
         <settings-camera id="camera"
             camera-active="[[isCameraActive_(cameraPresent_, selectedItem_)]]"
             on-phototaken="onPhotoTaken_">
         </settings-camera>
       </div>
     </div>
   </template>
   <script src="change_picture.js"></script>
 </dom-module>