fix segfault

If the main planner fails, res.trajectory_ is NULL, and accessing it segfaults.
Now, bail out in this case.

moveit_planners/chomp/chomp_optimizer_adapter/src/chomp_optimizer_adapter.cpp

@@ -166,7 +166,8 @@ class OptimizerAdapter : public planning_request_adapter::PlanningRequestAdapter
   {
     // following call to planner() calls the OMPL planner and stores the trajectory inside the MotionPlanResponse res
     // variable which is then used by CHOMP for optimization of the computed trajectory
-    bool solved = planner(ps, req, res);
+    if (!planner(ps, req, res))
+      return false;
 
     // create a hybrid collision detector to set the collision checker as hybrid
     collision_detection::CollisionDetectorAllocatorPtr hybrid_cd(
@@ -216,7 +217,7 @@ class OptimizerAdapter : public planning_request_adapter::PlanningRequestAdapter
       res.planning_time_ = res_detailed.processing_time_[0];
     }
 
-    return solved;
+    return planning_success;
   }
 
 private: