Li Jie

Splitted `template exec` to two definitions: ```nim template exec*(args: varargs[string, `$`]; inner: untyped) template exec*(args: seq[string]; inner: untyped) ``` It works.

@juancarlospaco So what is the reason? Does the Nim compiler has a break change? I'm not sure it's a good way, too many template methods need to change.

我先把 RNTester 改成 Promise 方式调用，已经跑起来了。但是 Touchable* 貌似有点问题。 

I am not sure if there is a way to directly specify includeMetadataChanges when constructing the `query`. If there is such a method, then this PR is unnecessary.

> @cpunion - This seems good to me. I think we should also update here: https://github.com/firebase/FirebaseUI-Flutter/blob/main/packages/firebase_ui_firestore/lib/src/table_builder.dart#L267 > > Probably should be able to pass it into `FirestoreDataTable` if you could...

> @cpunion - We can leave that for another time. Do you mind adding a simple test that passes in `includeMetadataChanges` and checks that metadata is passed in with snapshot...

@russellwheatley It seems that metadata changes too quickly to be captured by `tester.pump*`. For example, when creating and updating a document, `collection.snapshots().listen(includeMetadataChanges: true)` will receive a series of events in...

@russellwheatley I just added debug prints at https://github.com/firebase/FirebaseUI-Flutter/pull/349/files#diff-df489d5e040c259b77c51b59326d57ffa8ebbf45b0bee42e7bc1d257ab3ea68eR183 , so I think that is not testable.

@aykevl Updated SVD files.

Same. Should drop extensions before dropping types.