Fix setting the mode on a ClutterAlpha created with animation_set_alpha(NULL)
Fix setting the mode on a ClutterAlpha created with animation_set_alpha(NULL)

It previously attempted to set the mode on the alpha using
clutter_animation_set_mode_internal, but this was setting the mode on
priv->alpha. At that point in the code priv->alpha is always NULL.

clutter_animation_set_mode_internal now takes a parameter to specify
which alpha to modify.

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