Make chrome/ be documentElement/body agnostic with regards to scrollTop/Left

Blink is in the process of getting itself in pair with how other Web engines'
(Trident,Gecko,Presto) behavior with regards to scrollTop and scrollLeft when
called for documentElement and body. This process has been proved itself
to be of great impact within Chrome, given that its UI is written in HTML/JS/CSS.
See for example bugs 305800, 304753, 305745, 304816, 305742, 305092.

This CL tries to prevent Chrome from future similar breakages, as the Blink process
of adapting to this change is not yet 100% finalized. It will also allow CLs 69143002 and 51553002  to land without breaking Chrome.

CL also fixes driven-by issues like the usage of getElementById instead of $, so CQ can land the CL.

Additionally, a PRESUBMIT hook is being considered as well, in order to
advice programmers to not user {documentElement.body}.scroll{Top,Left} directly
and instead use the helper added to resources/js/util.js


BUG=316722
R=dbeam@chromium.org,newt@chromium.org,sky@chromium.org

Review URL: https://codereview.chromium.org/68723003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235414 0039d316-1c4b-4281-b951-d872f2087c98
<webview> Reclaim compositor resources released in the parent.

BUG=

Review URL: https://codereview.chromium.org/69013006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235415 0039d316-1c4b-4281-b951-d872f2087c98
lsan: Removed leak suppression in cc_unittests

This patch removes leak suppressions for leaks fixed in r234840

BUG=317970, 317969

Review URL: https://codereview.chromium.org/69933012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235416 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 235416