Don't call invalidateIntrinsicContentSize() unless necessary (#2782)

I've seen a severe problem where we're triggering
infinite layouts because the frame is reporting
changes when nothing has changed.

Co-authored-by: Jesse Wilson <jwilson@squareup.com>

Author: swankjesse

redwood-widget/src/iosMain/kotlin/app/cash/redwood/widget/RedwoodUIView.kt

@@ -147,11 +147,13 @@ public open class RedwoodUIView : RedwoodView<UIView> {
 
     private var widthForIntrinsicSize = UIViewNoIntrinsicMetric
       set(value) {
+        if (value == field) return // Don't invalidateIntrinsicContentSize() if nothing's changed.
         field = value
         invalidateIntrinsicContentSize()
       }
     private var heightForIntrinsicSize = UIViewNoIntrinsicMetric
       set(value) {
+        if (value == field) return // Don't invalidateIntrinsicContentSize() if nothing's changed.
         field = value
         invalidateIntrinsicContentSize()
       }