[Most Visited] Support two additional parameters in the iframes

chrome/browser/resources/local_ntp/most_visited_util.js

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 /**
  * @fileoverview Utilities for rendering most visited thumbnails and titles.
  */
 
 <include src="instant_iframe_validation.js">
@@ skipping 78 matching lines @@
   return params;
 }
 
 
 /**
  * Creates a new most visited link element.
  * @param {Object} params URL parameters containing styles for the link.
  * @param {string} href The destination for the link.
  * @param {string} title The title for the link.
  * @param {string|undefined} text The text for the link or none.
+ * @param {string|undefined} direction The text direction.
  * @param {string|undefined} provider A provider name (max 8 alphanumeric
  *     characters) used for logging. Undefined if suggestion is not coming from
  *     the server.
  * @return {HTMLAnchorElement} A new link element.
  */
-function createMostVisitedLink(params, href, title, text, provider) {
+function createMostVisitedLink(params, href, title, text, direction, provider) {
   var styles = getMostVisitedStyles(params, !!text);
   var link = document.createElement('a');
   link.style.color = styles.color;
   link.style.fontSize = styles.fontSize + 'px';
   if (styles.fontFamily)
     link.style.fontFamily = styles.fontFamily;
+  if (styles.textAlign)
+    link.style.textAlign = styles.textAlign;
+  if (styles.textFadePos) {
+    var dir = /^rtl$/i.test(direction) ? 'to left' : 'to right';
+    // The fading length in pixels is passed by the caller.
+    var mask = 'linear-gradient(' + dir + ', rgba(0,0,0,1), rgba(0,0,0,1) ' +
+        styles.textFadePos + 'px, rgba(0,0,0,0))';
+    link.style.textOverflow = 'clip';
+    link.style.webkitMask = mask;
+  }
 
   link.href = href;
   link.title = title;
   link.target = '_top';
   // Exclude links from the tab order.  The tabIndex is added to the thumbnail
   // parent container instead.
   link.tabIndex = '-1';
   if (text)
     link.textContent = text;
   link.addEventListener('mouseover', function() {
@@ skipping 24 matching lines @@
     }
     // Else follow <a> normally, so transition type would be LINK.
   });
 
   return link;
 }
 
 
 /**
  * Decodes most visited styles from URL parameters.
- * - f: font-family
+ * - f: font-family.
  * - fs: font-size as a number in pixels.
+ * - ta: text-align property, as a string.
+ * - tf: specifying a text fade starting position, in pixels.
  * - c: A hexadecimal number interpreted as a hex color code.
  * @param {Object.<string, string>} params URL parameters specifying style.
  * @param {boolean} isTitle if the style is for the Most Visited Title.
  * @return {Object} Styles suitable for CSS interpolation.
  */
 function getMostVisitedStyles(params, isTitle) {
   var styles = {
     color: '#777',
     fontFamily: '',
     fontSize: 11
   };
   var apiHandle = chrome.embeddedSearch.newTabPage;
   var themeInfo = apiHandle.themeBackgroundInfo;
   if (isTitle && themeInfo && !themeInfo.usingDefaultTheme) {
     styles.color = convertArrayToRGBAColor(themeInfo.textColorRgba) ||
         styles.color;
   } else if ('c' in params) {
     styles.color = convertToHexColor(parseInt(params.c, 16)) || styles.color;
   }
   if ('f' in params && /^[-0-9a-zA-Z ,]+$/.test(params.f))
     styles.fontFamily = params.f;
   if ('fs' in params && isFinite(parseInt(params.fs, 10)))
     styles.fontSize = parseInt(params.fs, 10);
+  if ('ta' in params && /^[-0-9a-zA-Z ,]+$/.test(params.ta))
+    styles.textAlign = params.ta;
+  if ('tf' in params) {
+    var tf = parseInt(params.tf, 10);
+    if (isFinite(tf))
+      styles.textFadePos = tf;
+  }
   return styles;
 }
 
 
 /**
  * @param {string} location A location containing URL parameters.
  * @param {function(Object, Object)} fill A function called with styles and
  *     data to fill.
  */
 function fillMostVisited(location, fill) {
@@ skipping 44 matching lines @@
   if (navigator.sendBeacon) {
     navigator.sendBeacon(url);
   } else {
     // if sendBeacon is not enabled, we fallback for "a ping".
     var a = document.createElement('a');
     a.href = '#';
     a.ping = url;
     a.click();
   }
 }