[analyzer] Block-terminators in value-places

[Simn]

Currently the analyzer rejects terminators in value-places:

class Main {
    static function main() {}

    static function test1() {
        var __return = function(x:Dynamic) { return 1; }
        __return(throw null); // Cannot use this expression as value
    }

    static function test2() {
        var __return = function(x:Dynamic) { return 1; }
         __return(return null); // Cannot use this expression as value
    }

    static function test3() {
        var __return = function(x:Dynamic) { return 1; }
        while (true) {
            __return(break); // Cannot use this expression as value
        }
    }

    static function test4() {
        var __return = function(x:Dynamic) { return 1; }
        while (true) {
            __return(continue); // Cannot use this expression as value
        }
    }
}

Instead of erroring we can simply add them as a block-element.