Call preventDefault in all on-tap events that show a dialog.

chrome/browser/resources/settings/site_settings/site_data.js

Index: chrome/browser/resources/settings/site_settings/site_data.js
diff --git a/chrome/browser/resources/settings/site_settings/site_data.js b/chrome/browser/resources/settings/site_settings/site_data.js
index c5df0d69c512672b5fb55d271b8efc7cc30b31ef..ab87956c66256e9e918dbc3ba5a8ea3af5472d7f 100644
--- a/chrome/browser/resources/settings/site_settings/site_data.js
+++ b/chrome/browser/resources/settings/site_settings/site_data.js
@@ -75,9 +75,11 @@ Polymer({
 
   /**
    * Shows a dialog to confirm the deletion of multiple sites.
+   * @param {!Event} e
    * @private
    */
-  onConfirmDeleteMultipleSites_: function() {
+  onConfirmDeleteMultipleSites_: function(e) {
+    e.preventDefault();
     this.idToDelete_ = '';  // Delete all.
     this.confirmationDeleteMsg_ = loadTimeData.getString(
         'siteSettingsCookieRemoveMultipleConfirmation');