GTK: reduce cpu usage of upgrade notification animation.

GTK: reduce cpu usage of upgrade notification animation.

First, don't queue excessive draws when the animation isn't changing. This should reduce cpu usage by about 75%.
Second, don't animate the little dot when the browser window isn't active. For WMs that support _NET_ACTIVE_WINDOW, this should keep CPU usage steady no matter how many browser windows are open.

The net effect of this patch is to reduce CPU usage from 100% in certain cases (when many windows are open) to a negligible amount (on metacity on my workstation).

BUG=48909
TEST=open many windows and inspect CPU usage according to top

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=52271

[tony, 2010-07-13 22:09:46]

LGTM

http://codereview.chromium.org/2985006/diff/5001/6003
File chrome/browser/gtk/browser_window_gtk.cc (right):

http://codereview.chromium.org/2985006/diff/5001/6003#newcode336
chrome/browser/gtk/browser_window_gtk.cc:336:
ActiveWindowWatcherX::AddObserver(this);
What is the reason for this move?  Should there be a comment explaining why this
needs to happen first?

[Evan Stade, 2010-07-13 22:29:40]

http://codereview.chromium.org/2985006/diff/5001/6003
File chrome/browser/gtk/browser_window_gtk.cc (right):

http://codereview.chromium.org/2985006/diff/5001/6003#newcode336
chrome/browser/gtk/browser_window_gtk.cc:336:
ActiveWindowWatcherX::AddObserver(this);
On 2010/07/13 22:09:47, tony wrote:
> What is the reason for this move?  Should there be a comment explaining why
this
> needs to happen first?

the reason is so that the observer gets called first and is_active() will be
updated by the time BrowserToolbarGtk is called back. I will add a comment.