Previously the renderers were fixed so that they inserted extra
"adjacent" statements after the last static property of classes.
In order to help the build-optimizer (in Angular CLI) to be able to
tree-shake classes effectively, these statements should also appear
after any helper calls, such as `__decorate()`.
This commit moves the computation of this positioning into the
`NgccReflectionHost` via the `getEndOfClass()` method, which
returns the last statement that is related to the class.
FW-1668
PR Close#33689