Allow getting StyledText content as html via getData

The key is simply StyledText.getData
Let's have this one as hidden "gem" for testing purposes to ease both
testing the implementation and may one day it would be worth exposing as
proper API.

Author: akurtakov

bundles/org.eclipse.swt/Eclipse SWT Custom Widgets/common/org/eclipse/swt/custom/StyledText.java

@@ -10935,4 +10935,13 @@ public static void updateAndRefreshCarets(StyledText styledText, Consumer<Caret>
 
 }
 
+@Override
+public Object getData(String key) {
+	if ("StyledText.htmlText".equals(key)) {
+		HTMLWriter htmlWriter = new HTMLWriter(this, 0, content.getCharCount(), content);
+		return getPlatformDelimitedText(htmlWriter);
+	}
+	return super.getData(key);
+}
+
 }