Broaden justify-self's parsing name

This is in preparation of migrating align-self, align-items
and justify-items to the CSS 3 Alignment syntax.

The current naming was too tied to justify-self and needs to
be broadened. This will reduce the follow-up implementations'
patches.

BUG=249451

Review URL: https://codereview.chromium.org/131773002

git-svn-id: svn://svn.chromium.org/blink/trunk@164817 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Don't cycle through subsequent siblings in clearFloatsIfNeeded()

When we encountered a self-collapsing block with clearance we were
cycling through subsequent siblings to determine if they were all self-collapsing.
That being the case we set a bit in MarginInfo to prevent the parent collapsing
its margins with the last child. It's better to set a bit when we encounter
a self-collapsing block with clearance and then reset it if we encounter a
block with height that allows the parent to collapse margins again.

This will allow us to ASSERT(!selfNeedsLayout()) in RenderBlock::isSelfCollapsingBlock().

BUG=

Review URL: https://codereview.chromium.org/124483002

git-svn-id: svn://svn.chromium.org/blink/trunk@164819 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove Attr.isId and Attr.ownerElement.

These properties were removed in DOM4
<http://dom.spec.whatwg.org/#interface-attr>. Use counters
AttributeIsId and AttributeOwnerElement indicate they're rarely used
on the web (<0.01%.)

BUG=305105

Review URL: https://codereview.chromium.org/124643003

git-svn-id: svn://svn.chromium.org/blink/trunk@164820 bbb929c8-8fbe-4397-9dbb-9b2b20218538
More WTF collections garbage collection support

R=ager@chromium.org, cevans@chromium.org, haraken@chromium.org, vegorov@chromium.org, wibling@chromium.org, zerny@chromium.org
BUG=

Review URL: https://codereview.chromium.org/127993002

git-svn-id: svn://svn.chromium.org/blink/trunk@164821 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Handle loops in audio graph better for PannerNodes

When a PannerNode searches the graph for audio sources connected to
the panner, prevent feedback loops from causing infinite loops.
Create a hashmap to keep track of all visited nodes so we don't visit
them more than once.

A test is also added to ensure we don't infloop.

BUG=331446

Review URL: https://codereview.chromium.org/130003002

git-svn-id: svn://svn.chromium.org/blink/trunk@164822 bbb929c8-8fbe-4397-9dbb-9b2b20218538