tree a57531ce6e50cfee3b0191ea712f06ccd1ecda27
parent 782c20b084f454b6a2f1fdd86d62b848cc3cc3eb
author wangxianzhu@chromium.org <wangxianzhu@chromium.org@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1342227176 +0000
committer wangxianzhu@chromium.org <wangxianzhu@chromium.org@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1342227176 +0000

[Chromium] Sometimes bottom of text is truncated when page has a fractional scale
https://bugs.webkit.org/show_bug.cgi?id=88684

Reviewed by Tony Chang.

Source/WebCore:

When the page has a fractional scale, the ascent and descent part of the fonts might be fractional.
If the descent part is rounded down, the bottom of the text might be truncated when displayed
when subpixel text positioning is enabled.
To avoid that, borrow one unit from the ascent when possible.

Test: fast/text/descent-clip-in-scaled-page.html

* platform/graphics/harfbuzz/FontPlatformDataHarfBuzz.cpp:
(WebCore::FontPlatformData::setupPaint): Moved NoPreference handling into querySystemForRenderStyle so that fontRenderStyle() can have actual styles without NoPreference.
(WebCore::FontPlatformData::querySystemForRenderStyle): Added NoPreference handling (moved from setupPaint)
* platform/graphics/harfbuzz/FontPlatformDataHarfBuzz.h:
(FontPlatformData):
(WebCore::FontPlatformData::fontRenderStyle): Added to let SimpleFontDataSkia access the font render styles.
* platform/graphics/skia/SimpleFontDataSkia.cpp:
(WebCore::SimpleFontData::platformInit):

LayoutTests:

New test case.

* fast/text/descent-clip-in-scaled-page-expected.html: Added.
* fast/text/descent-clip-in-scaled-page.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@122651 268f45cc-cd09-0410-ab3c-d52691b4dbfc