refactor(android): merge layout JS calls into a single call

> [...] It seems like part of the problem here is the existing spaghetti is making it very difficult to reason about the orientation state.
>
> One simple refactor I think we should try and apply is to reduce the number of `loadJavascript` calls:
>
> * Each call is costly
> * If we have a `setDimensions` function which is passed an object, then we can set as many of the dimensions as are passed in, in the specific order that they should be set, and without having to bubble that ordering detail all the up into the Java code.
> * It helps us see where we are only setting width or height or vice-versa.

_Originally posted by @mcdurdin in https://github.com/keymanapp/keyman/pull/11722#pullrequestreview-2103479072_

> This smells like it should be a single function call, `setDimensions({bannerHeight:%d,oskWidth:%d,oskHeight:%d})`.
>
> This may also be relevant:
https://github.com/keymanapp/keyman/blob/91e91bf91b56efb6cc20ebabd4a6f0a257801af0/android/KMEA/app/src/main/java/com/keyman/engine/KMKeyboard.java#L426-L436
>
> Calls to these functions (on master branch):
> * Only 1 call to `setBannerHeight`, right here.
> * 4 calls to `setOskHeight`
> * 2 calls to `setOskWidth`

_Originally posted by @mcdurdin in https://github.com/keymanapp/keyman/pull/11722#discussion_r1630512393_