Adapt usages in SWT to new GC#drawImage API

[arunjose696]

The new drawImage method has been introduced in eclipse-platform/eclipse.platform.swt#2548 that allows drawing the full image into a specified destination rectangle without requiring source bounds.

Previously, consumers needed to call image.getBounds() to determine the image dimensions and use this in the drawImage() call for drawing. The consumers drawing the image fully could adapt the new API and not call getBounds to get the image size.

[HeikoKlare]

I propose to also check whether it makes sense to replace the ImageDataProvider with an ImageDataAtSizeProvider at those places. For that reason, it makes sense to work on (or at least to finalize this) this after:

• Extend ImageDataAtSizeProvider support to MacOS #466
• Extend ImageDataAtSizeProvider support to Linux #467

Still, this is not blocked by those issues but I rather propose to assign an according priority (medium to this) to implicitly process them in reasonable order.