[misc][XWALK-1847] Replace picture URL in Resource Timing

- Old picture URL is invalid now, so need to relpace.

Impacted TCs num(approved): New 0, Update 1, Delete 0
Unit test Platform: Tizen M0
Tizen test result summary: Pass 1, Fail 0, Blocked 0
Merge pull request #341 from xinliux/xinliux/misc/xwalk-1847

[misc][XWALK-1847] Replace picture URL in Resource Timing