When to use past tense on event listener?

When should I use past tense on event listener? If you check the android link below, you can see onFocusChange on View and onFocusChanged on WebView. Which one should be more appropriate and why android choose present tense on view and pass tense on webview?

http://ift.tt/1DqmuOA

http://ift.tt/n3XOKe