Files in WebCore/bridge/jni are named incorrectly. They use lower case with underscores, rather than title case. Also, many of the files are for classes named JavaFoo, so should be renamed to match. This also brings up the related question of whether WebCore/bridge/jni should be renamed to WebCore/bridge/java to match the bridges to other languages?
Also, this code uses 'Runtime' in both class names and file names. This should be updated to use the more modern term 'Bridge'. See https://bugs.webkit.org/show_bug.cgi?id=33672#c8