[DirectWrite] Change minimum antialiased size for SimSun to 11px

Change the minimum size at which antialiasing is enabled for the SimSun
font to 11px. This ensures higher quality rendering at sizes where the
font is legible with GDI-style AA.

BUG=384091
R=cpu@chromium.org

Review URL: https://codereview.chromium.org/348603005

git-svn-id: svn://svn.chromium.org/blink/trunk@177233 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Use IDL default argument value for Range.collapse()'s toStart argument

Replace the existing [Default=Undefined] extended attribute, which since
undefined coerces to false means the same thing, with the actual default
value that's in the specification.

BUG=258153

Review URL: https://codereview.chromium.org/356103003

git-svn-id: svn://svn.chromium.org/blink/trunk@177235 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Remove usages of global HeapProfilerAgent

BUG=

Review URL: https://codereview.chromium.org/361713002

git-svn-id: svn://svn.chromium.org/blink/trunk@177236 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Devtools gardening: mark console-viewport-selection.html as flaky

BUG=390204
TBR=lushnikov

Review URL: https://codereview.chromium.org/360753002

git-svn-id: svn://svn.chromium.org/blink/trunk@177237 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Fix usage of global RuntimeAgent in ObjectPopoverHelper

BUG=

Review URL: https://codereview.chromium.org/336313016

git-svn-id: svn://svn.chromium.org/blink/trunk@177238 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Refactor emphasis mark code in InlineTextBox.

The duplication here is confusing; this separates a new paintEmphasisMark
function which contains the common logic.

Review URL: https://codereview.chromium.org/354263003

git-svn-id: svn://svn.chromium.org/blink/trunk@177239 bbb929c8-8fbe-4397-9dbb-9b2b20218538