#93793: Increased performance of dragging CanvasRenderer-based layers by activating and deactivating the mouse move event on the map when starting and endind the map dragging, respectively. We also only add the handling event once per canvas, which prevents adding the event handler with each render so event launches don't proliferate. The mouse move event was a big performance blocker as shown by the Chrome developers tool CPU profile recording.
We render the layer once added.
Tests modifications.
Merge pull request #33 from luisromangz/93793-CanvasRendererDraggingPerformanceImprovements

#93793 canvas renderer dragging performance improvements