Enable hash-based text autosizing.

Enable hashing in the text autosizer. The main impact of this
change enables consistent autosizing of forums and text within
similar table cells (see e.g. crbug.com/135947).

This change is pretty significant though and is expected to
result in some differences as compared with the current autosizer.
However testing on top-2K websites indicates there are no major
anomalies.

BUG=329904,334228,135947

Review URL: https://codereview.chromium.org/148383008

git-svn-id: svn://svn.chromium.org/blink/trunk@166032 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Unreviewed gardening, mark perf/compositor-touch-hit-rects.html flaky on all platforms

Saw some failures on release for this test previously marked flaky
only on debug, so I created a new bug for this flaky test and marked
it flaky on release.

TBR=rbyers@chromium.org
BUG=339118

Review URL: https://codereview.chromium.org/131103022

git-svn-id: svn://svn.chromium.org/blink/trunk@166033 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove the media attribute from the resource selection algorithm

Intent to Deprecate and Remove:
https://groups.google.com/a/chromium.org/d/msg/blink-dev/5sWUMC_d8Tg/ZZ0Z7rfeCqUJ

The HTMLSourceElement.media IDL attribute is left dangling, but a
UseCounter will be added for it in a separate commit, with the
intention to remove it once we have the data to support it.

BUG=338197

Review URL: https://codereview.chromium.org/147933002

git-svn-id: svn://svn.chromium.org/blink/trunk@166034 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: [CSS] cleaning-up CSS Domain in protocol.json

This patch slightly cleans-up CSS Domain in protocol.json without
affecting inspector front-end.

BUG=

Review URL: https://codereview.chromium.org/142413003

git-svn-id: svn://svn.chromium.org/blink/trunk@166035 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add the GeometricPrecisionDisablesTypesettingFeatures flag

This patch adds the runtime enabled feature "GeometricPrecisionDisablesTypesettingFeatures"
which disables kerning and ligatures for text with text-rendering=
geometricPrecision. This matches the spec [1]. If there are no major
regressions we will remove this flag in roughly 6 weeks (~1 release).

[1] https://svgwg.org/svg2-draft/single-page.html#painting-TextRenderingProperty

BUG=338870

Review URL: https://codereview.chromium.org/141433027

git-svn-id: svn://svn.chromium.org/blink/trunk@166037 bbb929c8-8fbe-4397-9dbb-9b2b20218538