Merge 94508 - <rdar://problem/10071256> Retain retired custom fonts until the next style recalc

Merge 94508 - <rdar://problem/10071256> Retain retired custom fonts until the next style recalc

Reviewed by Darin Adler.

Source/WebCore: 

Test: fast/css/font-face-used-after-retired.html

During style recalc, existing renderers may reference their old style, including font data.
Allow them to do so safely by keeping retired custom font data around until after style recalc.

* css/CSSFontFace.cpp:
(WebCore::CSSFontFace::retireCustomFont): Added. Calls through to CSSFontSelector, if the font
face is still part of any segmented font face. Otherwise, deletes the custom font data.
* css/CSSFontFace.h:
* css/CSSFontFaceSource.cpp:
(WebCore::CSSFontFaceSource::pruneTable): Changed to call retireCustomFont() instead of deleting
retired font data.
* css/CSSFontSelector.cpp:
(WebCore::CSSFontSelector::retireCustomFont): Added. Calls through to the Document, if this is
still the active font selector for a document. Otherwise, deletes the custom font data.
* css/CSSFontSelector.h:
* css/CSSSegmentedFontFace.cpp:
(WebCore::CSSSegmentedFontFace::pruneTable): Changed to call retireCustomFont() instead of
deleting retired font data.
* dom/Document.cpp:
(WebCore::Document::~Document): Added a call to deleteRetiredCustomFonts(), in case the Document
is destroyed before getting a chance to recalc style after custom fonts have been retired.
(WebCore::Document::recalcStyle): Added a call to deleteRetiredCustomFonts() after style recalc.
(WebCore::Document::deleteRetiredCustomFonts): Added. Deletes all previously-retired custom font
data.
* dom/Document.h:
(WebCore::Document::retireCustomFont): Added.

LayoutTests: 

* fast/css/font-face-used-after-retired-expected.txt: Added.
* fast/css/font-face-used-after-retired.html: Added.



TBR=mitz@apple.com
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=95345