Operators are inconsistent with block expressions

[tobil4sk]

Example:

final b = a + {final x = 10; x * x;}; // this is fine
final b = {final x = 10; x * x;} + a; // this is a compiler error: "characters 34-35 : Expected }"
final b = ({final x = 10; x * x;}) + a; // this on the other hand is fine too.

I discovered this by coming across a similar example to the one displayed in the example below, which is preventing ufront from compiling with haxe 4: https://github.com/ufront/ufront/issues/28

@:callable
abstract Function(Int->Int) to Int->Int from Int->Int {
	@:op(a + b)
	static function add(a:Function, b:Function):Function {
		return (i) -> a(b(i));
	}
}

class Test {
	static function main() {
		final f:Function = (a) -> a + 1;
		final g = ((a) -> {a * a;}) + f; // no issue here
		final h = (a) -> {a * a;} + f; // Test.hx:13: characters 30-31 : Expected }

		trace(g(10));
		trace(h(10));
	}
}