Support setVirtualPath for thread-model wrt-service

Support setVirtualPath for thread-model wrt-service

thread-model wrt-service runs all service application on worker
thread as daemon process.

For the virtual path resolving, it cannot get service application's
path. i.e. /home/owner/apps_rw/{service_app_pkgid}/data, becuase
wrt-service is org.tizen.chromium-efl package.

Thus, setting virtual path will be set by wrt-service framework
before each node worker thread started.
 - node worker has own V8 context

Change-Id: I8dd5e524584ebe71416c86c1e8648a2c4cfc4b94
Signed-off-by: DongHyun Song <dh81.song@samsung.com>