Fix memory leaks in rclcpp (#354)

* Make sure to delete service_handle when in the Service() destructor.

Signed-off-by: Chris Lalancette <clalancette@openrobotics.org>

* Make sure to delete the allocated rcl_node on error paths.

This all happens *before* we setup the shared_ptr destructor,
so we have to hand delete in the error paths.

Signed-off-by: Chris Lalancette <clalancette@openrobotics.org>

* Move delete rcl_node up.

It turns out that we are always going to throw in that block,
and we never access rcl_node, so just delete it very early
on.

Signed-off-by: Chris Lalancette <clalancette@openrobotics.org>

rclcpp/include/rclcpp/service.hpp

@@ -172,6 +172,7 @@ public:
         (std::cerr << ss.str()).flush();
         rcl_reset_error();
       }
+      delete service_handle_;
     }
   }
 

rclcpp/src/rclcpp/node_interfaces/node_base.cpp

@@ -92,6 +92,8 @@ NodeBase::NodeBase(
     // Finalize the interrupt guard condition.
     finalize_notify_guard_condition();
 
+    delete rcl_node;
+
     if (ret == RCL_RET_NODE_INVALID_NAME) {
       rcl_reset_error();  // discard rcl_node_init error
       int validation_result;