First screen is recomposed twice on iOS

[pjBooms]

The following code snippet:

@Composable
fun App() {
    val value = remember(LocalDensity.current) {
        (1..100).random()
    }
    println("Density: ${LocalDensity.current}")
    println("value is $value")
}

results in the following output:

Density: DensityImpl(density=1.0, fontScale=1.0)
value is 15
Density: DensityImpl(density=3.0, fontScale=1.0)
value is 34

on iOS.

That may have side effects like in the #3766 issue.

We should initialize density to correct value before first composition to eliminate this.

[elijah-semyonov]

@dima-avdeev-jb
We need to defer the first recomposition until didMoveToWindow was called with non-nil window. That's when a correct density scale is available.