RFR: 8285217: [Android] Window's screen is not updated after native screen was disposed

[Jose Pereda]

This PR updates the screen for each window even for the case where the old screen has been disposed but there is a new screen instance found for such window.

This is the case of Android, where the lifecycle of the application allows destroying the native screen when the app goes to the background, and providing a new native screen, in case it comes back to the foreground. Before this PR, the screen for the window wasn't updated after returning from the background, and if orientation changes happened, the dimensions were wrong.

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Commit messages:
 - Update the screen for each window even after old screen being disposed

Changes: https://git.openjdk.java.net/jfx/pull/778/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jfx&pr=778&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8285217
  Stats: 4 lines in 1 file changed: 1 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jfx/pull/778.diff
  Fetch: git fetch https://git.openjdk.java.net/jfx pull/778/head:pull/778

PR: https://git.openjdk.java.net/jfx/pull/778