[MD History] Color tweaks.

chrome/browser/resources/md_history/side_bar.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-a11y-keys-behavior/iron-a11y-keys-behavior.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-ripple/paper-ripple.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-styles/color.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-styles/typography.html">
 <link rel="import" href="chrome://history/browser_service.html">
 <link rel="import" href="chrome://history/shared_style.html">
 
 <dom-module id="history-side-bar">
   <template>
     <style include="shared-style">
       :host {
         display: flex;
         height: 100%;
         overflow-x: hidden;
         overflow-y: auto;
         width: var(--side-bar-width);
       }
 
       :host([drawer]) {
         height: calc(100% - var(--toolbar-height));
       }
 
       div.separator {
-        background-color: rgba(0, 0, 0, 0.08);
+        background-color: var(--separator-color);
         flex-shrink: 0;
         height: 1px;
         margin: 8px 0;
       }
 
       #clear-browsing-data {
         justify-content: space-between;
       }
 
       #clear-browsing-data iron-icon {
         -webkit-margin-end: 20px;
         color: var(--paper-grey-400);
         height: 20px;
         margin-bottom: 10px;
         margin-top: 10px;
         width: 20px;
       }
 
       iron-selector {
         -webkit-user-select: none;
         background-color: transparent;
-        color: #5a5a5a;
+        color: var(--sidebar-unselected-color);
         display: flex;
         flex: 1;
         flex-direction: column;
         padding-top: 8px;
       }
 
       iron-selector > a {
         @apply(--paper-font-subhead);
         /* Ensure the focus outline appears correctly (crbug.com/655503). */
         -webkit-margin-end: 4px;
         -webkit-padding-start: 24px;
         align-items: center;
         box-sizing: border-box;
         color: inherit;
         cursor: pointer;
         display: flex;
         font-size: 14px;
         font-weight: 500;
         min-height: 48px;
         position: relative;
         text-decoration: none;
       }
 
       iron-selector > a.iron-selected {
-        color: var(--google-blue-500);
+        color: var(--link-color);
       }
 
       #spacer {
         flex: 1;
       }
 
       #footer {
-        color: var(--paper-grey-600);
+        color: var(--sidebar-footer-text-color);
         width: var(--side-bar-width);
       }
 
       #footer-text {
         -webkit-padding-end: 16px;
         -webkit-padding-start: 24px;
         line-height: 20px;
         margin: 24px 0;
       }
 
       #footer a {
-        color: var(--google-blue-700);
         text-decoration: none;
       }
     </style>
 
     <iron-selector id="menu" selected="{{selectedPage}}"
         selectable=".page-item" attr-for-selected="path"
         fallback-selection="history"
         on-iron-activate="onSelectorActivate_">
       <a href="/" class="page-item" path="history" on-click="onItemClick_">
         $i18n{historyMenuItem}
@@ skipping 13 matching lines @@
       </a>
       <div id="spacer"></div>
       <div id="footer" hidden="[[!showFooter]]">
         <div class="separator"></div>
         <div id="footer-text">$i18nRaw{sidebarFooter}</div>
       </div>
     </iron-selector>
   </template>
   <script src="chrome://history/side_bar.js"></script>
 </dom-module>