Fix mirroring with SVG fonts

Fix mirroring with SVG fonts
https://bugs.webkit.org/show_bug.cgi?id=77067

Patch by Philip Rogers <pdr@google.com> on 2012-02-02
Reviewed by Nikolas Zimmermann.

Source/WebCore:

SVG fonts were incorrectly handling mirrored characters in bidi text.
In this change I added the function createStringWithMirroredCharacters
which handles mirroring the characters when selecting glyphs for SVG
fonts. I also made a small cosmetic change in the function
charactersWithArabicForm, changing the bool parameter "mirror" to "rtl"
which better reflects what it actually does.

Several new tests were added to test mirroring with SVG fonts in the
presence of Arabic forms and non-BMP characters.

Tests: svg/custom/glyph-selection-arabic-forms.svg
       svg/custom/glyph-selection-bidi-mirror.svg
       svg/custom/glyph-selection-non-bmp.svg

* platform/graphics/SVGGlyph.cpp:
(WebCore::charactersWithArabicForm):
* svg/SVGFontData.cpp:
(WebCore::SVGFontData::applySVGGlyphSelection):
(WebCore::SVGFontData::createStringWithMirroredCharacters):
* svg/SVGFontData.h:
(SVGFontData):

LayoutTests:

SVG fonts were incorrectly handling mirrored characters in bidi text.
In this change I added the function createStringWithMirroredCharacters
which handles mirroring the characters when selecting glyphs for SVG
fonts. I also made a small cosmetic change in the function
charactersWithArabicForm, changing the bool parameter "mirror" to "rtl"
which better reflects what it actually does.

Several new tests were added to test mirroring with SVG fonts in the
presence of Arabic forms and non-BMP characters.

* svg/custom/glyph-selection-arabic-forms-expected.txt: Added.
* svg/custom/glyph-selection-arabic-forms.svg: Added.
* svg/custom/glyph-selection-bidi-mirror-expected.txt: Added.
* svg/custom/glyph-selection-bidi-mirror.svg: Added.
* svg/custom/glyph-selection-non-bmp-expected.txt: Added.
* svg/custom/glyph-selection-non-bmp.svg: Added.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@106551 268f45cc-cd09-0410-ab3c-d52691b4dbfc