Bug 65187 [Themes] Cascading*Registry leakage from Colors and Fonts pref page
Small leak on I20040529 For each ColorsAndFontsPreferencePage this is created, the cascading font and color registries are leaked. This is because the superclasses register a runnable with Display#disposeExec
bundles/org.eclipse.jface/src/org/eclipse/jface/resource/FontRegistry.java
* Return the italic Font. Create an italic version of the
         * base font to get it.
         * @return Font
         */
        public Font getItalicFont() {
            if (italicFont != null)
                return italicFont;
            FontData[] italicData = getModifiedFontData(SWT.ITALIC);
            italicFont = new Font(Display.getCurrent(), italicData);
            return italicFont;
        }
        /**
         * Add any fonts that were allocated for this record to the
         * stale fonts. Anything that matches the default font will
         * be skipped.
         * @param defaultFont The system default.
         */
        void addAllocatedFontsToStale(Font defaultFont) {
            
            
            if (defaultFont != baseFont && baseFont != null)
                staleFonts.add(baseFont);
            if (defaultFont != boldFont && boldFont != null)
                staleFonts.add(boldFont);
            if (defaultFont != italicFont && italicFont != null)
                staleFonts.add(italicFont);
        }
    }
    /**
     * Table of known fonts, keyed by symbolic font name