crisbeto c3e93564d0 perf(ivy): avoid generating selectors array for directives without a selector ()
Now that we've replaced `ngBaseDef` with an abstract directive definition, there are a lot more cases where we generate a directive definition without a selector. These changes make it so that we don't generate the `selectors` array if it's going to be empty.

PR Close 
2019-10-29 12:06:15 -07:00
..
2019-02-28 12:06:36 -08:00