Find/replace overlay: react to target relocation instead of paint events

[HeikoKlare]

The FindReplaceOverlay currently registers a paint listener to the target in order to reposition itself upon move or resize events of the parent (paint events subsume resize and move events). This has two drawbacks:

1. The update is performed too often, as paint events happen more often than move or resize events.
2. Due to limitations in Wayland, repositioning the overlay does not work there. A combination of processed repaint events and failing position updates even leads to the shell contents moving out of the shell.

This change replaces the repaint listener with a move and resize listener. In consequence, less (unnecessary) updates of the overlay's position and size are executed and on Wayland at least the shell contents do not move out of the window anymore.

Contributes to eclipse-platform/eclipse.platform.swt#1447

Behavior on Wayland

This change does not resolve the location problem of the overlay when using Wayland. That issue is not specific for the overlay but affect all shells/dialogs. It only works towards its contents not vanishing, thus improving usability of the overlay, even though its location is wrong.

Before change:

After change:

[github-actions]

Test Results

 1 815 files  ±0   1 815 suites  ±0   1h 29m 1s ⏱️ - 5m 57s
 7 697 tests ±0   7 469 ✅ ±0  228 💤 ±0  0 ❌ ±0 
24 252 runs  ±0  23 503 ✅ ±0  749 💤 ±0  0 ❌ ±0 

Results for commit 2f42b4d. ± Comparison against base commit 6368b06.

♻️ This comment has been updated with latest results.