DevTools: [Elements] Center focused tree element vertically when selecting inspected node in page

In order to avoid visual jitter, if an element is already visible in the tree, the scroll will not occur.

R=aandrey@chromium.org, pfeldman, vsevik
BUG=305562

Review URL: https://codereview.chromium.org/27002003

git-svn-id: svn://svn.chromium.org/blink/trunk@159447 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Web Animations CSS: Support animation of font-size

BUG=257591

Review URL: https://codereview.chromium.org/26320008

git-svn-id: svn://svn.chromium.org/blink/trunk@159448 bbb929c8-8fbe-4397-9dbb-9b2b20218538
FlameChart: Make draw function 10 times faster.

1) put all draw sensitive data into separate external arrays
2) mark particular pixel as painted and do not paint other bars if they
hit into the same pixel.

BUG=302913
R=alph@chromium.org

Review URL: https://codereview.chromium.org/25995003

git-svn-id: svn://svn.chromium.org/blink/trunk@159449 bbb929c8-8fbe-4397-9dbb-9b2b20218538