[webapi] Update the method name for Selectors API Level 2 due to spec update

- New spec: http://www.w3.org/TR/2013/NOTE-selectors-api2-20131017

Impacted tests(approved): new 0, delete 5, update 2
Unit test platform: [Android][IVI]
Unit test result summary: pass 19, fail 50, block 0

Comment: Test result is the same as upstream result