chrome://downloads updateDateDisplay more often

chrome/browser/resources/downloads/downloads.js

 // Copyright (c) 2012 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.
 
 // TODO(jhawkins): Use hidden instead of showInline* and display:none.
 
 /**
  * Sets the display style of a node.
  * @param {!Element} node The target element to show or hide.
  * @param {boolean} isShow Should the target element be visible.
@@ skipping 86 matching lines @@
     // We get downloads in display order, so we don't have to worry about
     // maintaining correct order - we can assume that any downloads not in
     // display order are new ones and so we can add them to the top of the
     // list.
     if (download.started > this.newestTime_) {
       this.node_.insertBefore(this.downloads_[id].node, this.node_.firstChild);
       this.newestTime_ = download.started;
     } else {
       this.node_.appendChild(this.downloads_[id].node);
     }
-    this.updateDateDisplay_();
   }
+  // Download.prototype.update may change its nodeSince_ and nodeDate_, so

[asanka, 2012/09/17 16:48:14]

Is nodeSince_ updated for all the download items after a clock adjustment?

[benjhayden, 2012/09/17 17:02:38]

Yes, downloads_dom_handler.cc since_string uses TimeFormat::RelativeDate(),
which calls Time::Now(), which tracks the system clock according to base/time.h.
But no, merely changing the clock doesn't trigger any events that
DownloadsDOMHandler watches for. The next time a download is created or
destroyed, all the items will be updated at once. A single OnDownloadUpdated
event without download creation or deletion might mean that one entry in
chrome://downloads reflects the new time but the rest don't. This fix at least
prevents there from being two 'Today' sections with the same date, though there
may be two 'Today' sections with different dates. I could probably hack some
javascript together to detect same since strings with different dates and call
getDownloads, but I think that the only way to get in this state (after this fix
is in) would be if you changed the system clock while a large file was actually
downloading or a dangerous file was waiting to be confirmed, which seems rare
and not worth the effort.

[asanka, 2012/09/17 17:50:14]

Yeah. I wasn't sure what the intended fix was. It seems there are other places
where we assume that downloads are created in wall clock order, and this issue
is partly about that assumption being false.

Also, it looks like TimeFormat::RelativeDate() will return 'Today' for all dates
that are in the future. So if there is a download in history with a start date
more than a day in the future, that item as well as any downloads that were in
fact started "today" will all get the 'Today' label. So even with this fix,
there would be two "Today" sections. Isn't it?

[benjhayden, 2012/09/17 18:09:42]

I like car analogies, even though I know next to nothing about cars.
This would be like propping your car up on blocks and running it in reverse
until the odometer ran negative. Of course the car wasn't driven -100 miles.
You're just asking it to lie to you.
I suppose we could detect future downloads and change the since string from
Today to 'Pass the sonic screwdriver' or 'Back... to the Future!' or some other
scifi reference.

+  // update all the date displays.
+  // TODO(benjhayden) Only do this if its nodeSince_ or nodeDate_ actually did
+  // change since this may touch 150 elements and Downloads.prototype.updated
+  // may be called 150 times.
+  this.updateDateDisplay_();
 };
 
 /**
  * Set our display search text.
  * @param {string} searchText The string we're searching for.
  */
 Downloads.prototype.setSearchText = function(searchText) {
   this.searchText_ = searchText;
 };
 
@@ skipping 626 matching lines @@
     if (Date.now() - start > 50) {
       clearTimeout(resultsTimeout);
       resultsTimeout = setTimeout(tryDownloadUpdatedPeriodically, 5);
       break;
     }
   }
 }
 
 // Add handlers to HTML elements.
 window.addEventListener('DOMContentLoaded', load);