Revert 164780 "Introduce TextFinder class for decoupling WebFram..."

> Introduce TextFinder class for decoupling WebFrameImpl and text finder.
> 
> It will be lazily initialized when user activates find on page functionality.
> 
> BUG=
> 
> Review URL: https://codereview.chromium.org/69923006

TBR=iceman@yandex-team.ru

Review URL: https://codereview.chromium.org/132563003

git-svn-id: svn://svn.chromium.org/blink/trunk@164801 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Move traverseLiveNodeListFirstElement() to LiveNodeList class

Move traverseLiveNodeListFirstElement() to LiveNodeList class and rename to
traverseToFirstElement() for consistency with
HTMLCollection::traverseToFirstElement(). Also handle ChildNodeList in
LiveNodeList::traverseToFirstElement() as ChildNodeList is a LiveNodeList and
there is no reason to treat it differently from the other LiveNodeList
subclasses.

R=eseidel

Review URL: https://codereview.chromium.org/108343008

git-svn-id: svn://svn.chromium.org/blink/trunk@164802 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Update HTML forms classes to use OVERRIDE / FINAL when needed

Update HTML forms classes to use OVERRIDE / FINAL when needed. Those are
useful for error checking or performance when the compiler supports it.

R=esprehn, abarth
BUG=None

Review URL: https://codereview.chromium.org/132103002

git-svn-id: svn://svn.chromium.org/blink/trunk@164803 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Consolidate shouldMoveToFlowThread() into RenderTreeBuilder

This patch removes the callback from Element and SVGElement and puts the logic
into RenderTreeBuilder. This means less of the code base needs to know about
regions and also removes another "C++ backdoor" so that future elements don't
use this hook and could possibly be implemented as web components.

Review URL: https://codereview.chromium.org/127753004

git-svn-id: svn://svn.chromium.org/blink/trunk@164804 bbb929c8-8fbe-4397-9dbb-9b2b20218538
PartitionAlloc: cleanup, remove root pointer from bucket.

This is another piece extracted from already reviewed but reverted CL:
https://codereview.chromium.org/105503009/

TBR=tsepez@chromium.org
BUG=327095

Review URL: https://codereview.chromium.org/132343005

git-svn-id: svn://svn.chromium.org/blink/trunk@164805 bbb929c8-8fbe-4397-9dbb-9b2b20218538