Bugfix: Selecting AnimData "expanders" in AnimEditors works again

Somewhere along the line, this functionality broke, even though the code to
handle these settings was still in place for many of these. The main implication
of this fix is that it should now be possible to select a particular AnimData
block, which makes it possible to do things such as changing the action
associated with that AnimData block (i.e. via the "Animation Data" panel in the
NLA Editor), as well as other operations which I've had on the todolist for a
while. Stay tuned!

source/blender/editors/animation/anim_channels_defines.c

@@ -381,6 +381,10 @@ static short acf_generic_dataexpand_setting_valid(bAnimContext *ac, bAnimListEle
 		case ACHANNEL_SETTING_MUTE:
 			return ((ac) && (ac->spacetype == SPACE_NLA));
 			
+		/* select is ok for most "ds*" channels (e.g. dsmat) */
+		case ACHANNEL_SETTING_SELECT:
+			return 1;
+			
 		/* other flags are never supported */
 		default:
 			return 0;

source/blender/editors/space_nla/nla_channels.c

@@ -140,7 +140,7 @@ static int mouse_nla_channels(bAnimContext *ac, float x, int channel_index, shor
 				}
 				else {
 					Base *b;
-
+					
 					/* deselect all */
 					/* TODO: should this deselect all other types of channels too? */
 					for (b = sce->base.first; b; b = b->next) {

source/blender/editors/space_nla/nla_draw.c

@@ -759,7 +759,6 @@ static void draw_nla_channel_list_gl(bAnimContext *ac, ListBase *anim_data, View
 				glEnable(GL_BLEND);
 				
 				/* draw backing strip behind channel name */
-				// FIXME: hardcoded colors!!!
 				if (group == 5) {
 					float color[4];