WICKET-5243 JS: High stack size in Function Executor causes "too much recursion"

Execute the functions synchronously without allocation new stack frame (i.e. avoid recursion) when there is no need of such.
Only downloading of JS/CSS resources and execution of JS with manual control need to use the notify() call and recursion.

(cherry picked from commit 65f3a72eaa8c9c6796d217000e502367082a5154)
WICKET-5243 JS: High stack size in Function Executor causes "too much recursion"

Remove newly introduced test data and reuse the old one

(cherry picked from commit eac4109938d99f7fb77d6bb79ffdc7cff0f64b21)