Add support for 8 bit TextRuns for Chromium/HarfBuzz
https://bugs.webkit.org/show_bug.cgi?id=99393

Reviewed by Eric Seidel.

Source/WebCore:

Adding support for 8 bit TextRuns for platforms using HarfBuzz. To accomplish this,
8 bit text runs are upconverted to 16 bit in the complex text path during string
normalization, as HarfBuzz operates on UChars.

No new tests. No change in behavior.

(WebCore::HarfBuzzShaperBase::setNormalizedBuffer):
* platform/graphics/harfbuzz/HarfBuzzShaperBase.h:
* platform/graphics/harfbuzz/HarfBuzzShaper.cpp:
(WebCore::normalizeCharacters):
(WebCore::HarfBuzzShaper::HarfBuzzShaper):

Source/WebKit/chromium:

Enabling 8 bit text runs for Chromium.

* features.gypi:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@144065 268f45cc-cd09-0410-ab3c-d52691b4dbfc