[cogl-fbo] Bring the gles code more in line with gl code
[cogl-fbo] Bring the gles code more in line with gl code

Over time the two cogl-fbo.c files have needlessly diverged as bug fixes or
cleanups went into one version but not the other.  This tries to bring them
back in line with each other.  It should actually be simple enough to move
cogl-fbo.c to be a common file, and simply not build it for GLES 1.1, so
maybe I'll follow up with such a patch soon.

spatulasnout/clutter,GNOME/clutter,spatulasnout/clutter,collects/clutter,GNOME/clutter,djdeath/clutter-android,rkudiyarov/clutter_osx,spatulasnout/clutter,ebassi/clutter,Distrotech/clutter,kerrickstaley/clutter-vala,collects/clutter,ebassi/clutter,djdeath/clutter-android,Distrotech/clutter,kerrickstaley/clutter-vala,heysion/clutter-clone,heysion/clutter-clone,jigpu/clutter,spatulasnout/clutter,Distrotech/clutter,Distrotech/clutter,collects/clutter,djdeath/clutter-multithreaded,GNOME/clutter,ebassi/clutter,GNOME/clutter,ebassi/clutter,GNOME/clutter,dlespiau/clutter,jigpu/clutter,jigpu/clutter,djdeath/clutter-android,Distrotech/clutter,jigpu/clutter,djdeath/clutter,Distrotech/clutter,rkudiyarov/clutter_osx,collects/clutter,dlespiau/clutter,kerrickstaley/clutter-vala,jigpu/clutter,djdeath/clutter,jigpu/clutter,collects/clutter,djdeath/clutter-multithreaded,djdeath/clutter,nobled/clutter,nobled/clutter,heysion/clutter-clone,ebassi/clutter,djdeath/clutter-android,kerrickstaley/clutter-vala,spatulasnout/clutter,djdeath/clutter,heysion/clutter-clone,djdeath/clutter,djdeath/clutter-multithreaded,djdeath/clutter-android,rkudiyarov/clutter_osx,rkudiyarov/clutter_osx,djdeath/clutter-multithreaded,nobled/clutter,djdeath/clutter,heysion/clutter-clone,dlespiau/clutter