Fix bugs with baseline optimizing virtual test suites.

Some of the code is not covered by unittests since we mock out
_move_baselines. These were some places where we were double
including the virtual/foo directory. _join_directory, does
the right thing now.

Review URL: https://chromiumcodereview.appspot.com/21084008

git-svn-id: svn://svn.chromium.org/blink/trunk@155186 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove webkitNotifications.createHTMLNotification

This CL removes support for webkitNotifications.createHTMLNotification. This
API no longer works on any platform except Linux. We haven't exposed this API
to the web in a long time, but we've been keeping it around to support a
handful of Chrome extensions that were using the feature. These extensions have
now migrated to Rich Notifications
<http://blog.chromium.org/2013/05/rich-notifications-in-chrome.html>. As we've
implemented Rich Notifications on various platforms, we've been removing
support for createHTMLNotification. At this point, createHTMLNotification works
only on Linux.

This CL does not affect the text-based webkitNotifications.createNotification
or the unprefixed "new Notification" APIs, both of which will continue to
function after this CL.

BUG=137297

Review URL: https://chromiumcodereview.appspot.com/21087006

git-svn-id: svn://svn.chromium.org/blink/trunk@155187 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add window.internals.observeGC for leak-related tests.

The objective of this change is to make it possible to write unit
tests to detect leaks. The approach is to add a test hook, used like
this:

  var observation = window.internals.observeGC(value);

When value is "near death" during a garbage collection (perhaps
triggered in a test by calling gc()) then

  observation.wasCollected

is set to true. (Of course, it behooves the test writer not to create
a reference from observation to value.)

The reliability of this as a testing method is unproven. gc()
reportedly does seven garbage collections, so I think it will be
useful. The plan is to use this in Custom Elements leak tests; those
tests can be a litmus test for whether to keep this hook.

BUG=none
R=abarth@chromium.org, adamk@chromium.org

Review URL: https://codereview.chromium.org/21046002

git-svn-id: svn://svn.chromium.org/blink/trunk@155188 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add a test that Custom Elements do not induce leaks.

BUG=234509
R=abarth@chromium.org

Review URL: https://codereview.chromium.org/21060003

git-svn-id: svn://svn.chromium.org/blink/trunk@155189 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Improve timer alignment code when timer duration is near the alignment interval.

BUG=259680
R=esprehn@chromium.org,jamesr@chromium.org

Review URL: https://chromiumcodereview.appspot.com/19847002

git-svn-id: svn://svn.chromium.org/blink/trunk@155190 bbb929c8-8fbe-4397-9dbb-9b2b20218538