[TIZEN] Runtime has no chance to get remote debug flag

The first created Runtime has no chance to notify its application
(observer) to update its remote debug flag.

BUG=https://crosswalk-project.org/jira/browse/XWALK-3080
Merge pull request #2688 from wuyuehang/XWALK-3080

[TIZEN] Runtime has no chance to get remote debug flag