Bug 140400

Summary:	Downloading web fonts causes unnecessary font invalidation
Product:	WebKit	Reporter:	Myles C. Maxfield <mmaxfield>
Component:	Layout and Rendering	Assignee:	Myles C. Maxfield <mmaxfield>
Status:	NEW ---
Severity:	Normal
Priority:	P2
Version:	528+ (Nightly build)
Hardware:	Unspecified
OS:	Unspecified

Description Myles C. Maxfield 2015-01-13 11:43:05 PST

Every time a web font is downloaded, it calls CSSFontSelector::dispatchInvalidationCallbacks(), which increments m_version. This, in addition to RenderStyle::setFontDescription() always creating new Font objects, means that every time a web font finishes downloading, we throw out everything we know about fonts and regenerate everything.