Disable Clear Browsing Data button in History for guest profiles

chrome/browser/resources/md_history/side_bar.js

Index: chrome/browser/resources/md_history/side_bar.js
diff --git a/chrome/browser/resources/md_history/side_bar.js b/chrome/browser/resources/md_history/side_bar.js
index e0f7e13ad31582d00b8d81cf437613b61ce347b2..cfc0b9434896c861e74240b9263250353c4bac8f 100644
--- a/chrome/browser/resources/md_history/side_bar.js
+++ b/chrome/browser/resources/md_history/side_bar.js
@@ -13,6 +13,12 @@ Polymer({
       notify: true,
     },
 
+    /** @private */
+    guestSession_: {
+      type: Boolean,
+      value: loadTimeData.getBoolean('isGuestSession'),
+    },
+
     showFooter: Boolean,
   },
 
@@ -49,6 +55,14 @@ Polymer({
   },
 
   /**
+   * @return {number}
+   * @private
+   */
+  computeClearBrowsingDataTabIndex_: function() {
+    return this.guestSession_ ? -1 : 0;
+  },
+
+  /**
    * Prevent clicks on sidebar items from navigating. These are only links for
    * accessibility purposes, taps are handled separately by <iron-selector>.
    * @private