Avoid occasional DoF-related crash upon region disconnection.

indra/newview/pipeline.cpp

@@ -6784,7 +6784,7 @@ void LLPipeline::renderBloom(BOOL for_snapshot, F32 zoom_factor, int subfield, b
 												  NULL,
 												  &focus_point);
 				}
-				else
+				else if(gAgent.getRegion())
 				{
 					//focus on alt-zoom target
 					focus_point = LLVector3(gAgentCamera.getFocusGlobal()-gAgent.getRegion()->getOriginGlobal());