ntp4: record app launch source

chrome/browser/resources/ntp4/most_visited_page.js

 // Copyright (c) 2011 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.
 
 cr.define('ntp4', function() {
   'use strict';
 
   var TilePage = ntp4.TilePage;
 
   /**
@@ skipping 100 matching lines @@
 
     /**
      * Handles a click on the tile.
      * @param {Event} e The click event.
      */
     handleClick_: function(e) {
       if (e.target.classList.contains('close-button')) {
         this.blacklist_();
         e.preventDefault();
       } else {
+        // Records an app launch from the most visited page (Chrome will decide
+        // whether the url is an app).
+        // TODO(estade): don't convert to string.
+        chrome.send('recordAppLaunchByURL',

[Rick Byers, 2011/08/03 14:41:11]

Is replacing the ping with a click handler really equivalent?  I thought ping
was designed to handle a broader set of situations - eg. right click and "open
in new tab".  Too bad there's no "on anchor activate" DOM event - that's really
what you want I think.  I suppose we have to decide whether we'd rather use
pings, switch the anchors to plain divs, or miss out on some launches.

[Evan Stade, 2011/08/03 22:11:22]

I would have thought you were right, but ping doesn't seem to work that way
(open in new tab/window from the context menu doesn't send a ping).

Also, right click + open URL in new tab kind of sucks for recently closed,
because it doesn't restore session state (e.g. back/forward history).

[Rick Byers, 2011/08/04 00:32:21]

That sucks - seems like a bug according to the spec:
http://www.whatwg.org/specs/web-apps/current-work/multipage/links.html#hyperl....
 Anyway, it's your call, but I'd prefer if you at least left a comment pointing
out that the app launches are only recorded for regular clicks.  It might be
worth getting Arv's input on this when he's back.

+                    [this.href, String(ntp4.APP_LAUNCH.NTP_MOST_VISITED)]);
+        // Records the index of this tile.
         chrome.send('recordInHistogram', ['NTP_MostVisited', this.index, 8]);
       }
     },
 
     /**
      * Allow blacklisting most visited site using the keyboard.
      */
     handleKeyDown_: function(e) {
       if (!IS_MAC && e.keyCode == 46 || // Del
           IS_MAC && e.metaKey && e.keyCode == 8) { // Cmd + Backspace
@@ skipping 232 matching lines @@
     if (tile)
       tile.setStripeColor(color);
   };
 
   return {
     MostVisitedPage: MostVisitedPage,
     refreshData: refreshData,
     setFaviconDominantColor: setFaviconDominantColor,
   };
 });