Android: Rename image method to toImage.

toImage is a virtual method declared in QPlatformBackingStore and is
useful when you need to access the image buffer from outside the QPA
plugin. (e.g. you can use
QPlatformBackingStore::toImage().save("bs.png") to save it).

Change-Id: I7cc70ed295070707ed0ef3ce208129f174f68cfb
Reviewed-by: Paul Olav Tvete <paul.tvete@digia.com>
Fix multisampled fbo readback

Now that the current fbo is not tracked anymore, toImage() and
blitFramebuffer() will not restore the previously bound (or
whichever Qt thinks was current before) fbo. toImage() needs to
accommodate this since the isBound() check was going wrong now that
the blit always makes the fbo non-current.

The current fbo is now queried via glGet both in toImage() and
blitFramebuffer().

This will fix the recently introduced Lancelot failures with -glbuffer.

Change-Id: I43a780beaeac4697d92cb0ebda7d14ca28a3924f
Reviewed-by: aavit <eirik.aavitsland@digia.com>
Reviewed-by: Gunnar Sletta <gunnar.sletta@jollamobile.com>
Make the ICO image handler capable of reading CUR files too.

This simple patch was an unfortunate victim of the Gitorious to
Gerrit transition. (https://qt.gitorious.org/qt/qt/merge_requests/1179)

As noted in the Gitorious review, a small bug in readHeader is also fixed: ||
instead of &&.

Done-with: Pali Rohár
Task-number: QTBUG-12684
Change-Id: I1fe16359b9b68c10e518904c6a5c58b00fb7379b
Reviewed-by: Yoann Lopes <yoann.lopes@digia.com>