Use const-ref parameter for zeek::val_list_to_args()

It ended up being used a bit more than initially expected and this
is closer to the style we're generally aiming for.

src/Conn.cc

@@ -488,7 +488,7 @@ void Connection::Event(EventHandlerPtr f, analyzer::Analyzer* analyzer, Val* v1,
 
 void Connection::ConnectionEvent(EventHandlerPtr f, analyzer::Analyzer* a, val_list vl)
 	{
-	auto args = zeek::val_list_to_args(&vl);
+	auto args = zeek::val_list_to_args(vl);
 
 	if ( ! f )
 		// This may actually happen if there is no local handler
@@ -502,13 +502,13 @@ void Connection::ConnectionEvent(EventHandlerPtr f, analyzer::Analyzer* a, val_l
 void Connection::ConnectionEventFast(EventHandlerPtr f, analyzer::Analyzer* a, val_list vl)
 	{
 	// "this" is passed as a cookie for the event
-	mgr.Enqueue(f, zeek::val_list_to_args(&vl), SOURCE_LOCAL,
+	mgr.Enqueue(f, zeek::val_list_to_args(vl), SOURCE_LOCAL,
 	            a ? a->GetID() : 0, this);
 	}
 
 void Connection::ConnectionEvent(EventHandlerPtr f, analyzer::Analyzer* a, val_list* vl)
 	{
-	auto args = zeek::val_list_to_args(vl);
+	auto args = zeek::val_list_to_args(*vl);
 	delete vl;
 
 	if ( f )

src/Event.cc

@@ -99,14 +99,14 @@ void EventMgr::QueueEventFast(const EventHandlerPtr &h, val_list vl,
                               SourceID src, analyzer::ID aid, TimerMgr* mgr,
                               BroObj* obj)
 	{
-	QueueEvent(new Event(h, zeek::val_list_to_args(&vl), src, aid, obj));
+	QueueEvent(new Event(h, zeek::val_list_to_args(vl), src, aid, obj));
 	}
 
 void EventMgr::QueueEvent(const EventHandlerPtr &h, val_list vl,
                           SourceID src, analyzer::ID aid,
                           TimerMgr* mgr, BroObj* obj)
 	{
-	auto args = zeek::val_list_to_args(&vl);
+	auto args = zeek::val_list_to_args(vl);
 
 	if ( h )
 		Enqueue(h, std::move(args), src, aid, obj);
@@ -116,7 +116,7 @@ void EventMgr::QueueEvent(const EventHandlerPtr &h, val_list* vl,
                           SourceID src, analyzer::ID aid,
                           TimerMgr* mgr, BroObj* obj)
 	{
-	auto args = zeek::val_list_to_args(vl);
+	auto args = zeek::val_list_to_args(*vl);
 	delete vl;
 
 	if ( h )

src/Func.cc

@@ -296,7 +296,7 @@ int BroFunc::IsPure() const
 
 IntrusivePtr<Val> Func::Call(val_list* args, Frame* parent) const
 	{
-	return Call(zeek::val_list_to_args(args), parent);
+	return Call(zeek::val_list_to_args(*args), parent);
 	}
 
 IntrusivePtr<Val> BroFunc::Call(const zeek::Args& args, Frame* parent) const

src/ZeekArgs.cc

@@ -2,12 +2,12 @@
 #include "IntrusivePtr.h"
 #include "Val.h"
 
-zeek::Args zeek::val_list_to_args(const val_list* vl)
+zeek::Args zeek::val_list_to_args(const val_list& vl)
 	{
 	zeek::Args rval;
-	rval.reserve(vl->length());
+	rval.reserve(vl.length());
 
-	for ( auto& v : *vl )
+	for ( auto& v : vl )
 		rval.emplace_back(AdoptRef{}, v);
 
 	return rval;

src/ZeekArgs.h

@@ -17,11 +17,10 @@ using Args = std::vector<IntrusivePtr<Val>>;
  * Converts a legacy-style argument list for use in modern Zeek function
  * calling or event queueing APIs.
  * @param vl  the argument list to convert, the returned value takes ownership
- * of a reference to each element in the list, but not ownership of the list
+ * of a reference to each element in the list
- * itself.
  * @return  the converted argument list
  *
  */
-Args val_list_to_args(const val_list* vl);
+Args val_list_to_args(const val_list& vl);
 
 } // namespace zeek

src/analyzer/Analyzer.cc

@@ -803,7 +803,7 @@ void Analyzer::Event(EventHandlerPtr f, Val* v1, Val* v2)
 
 void Analyzer::ConnectionEvent(EventHandlerPtr f, val_list* vl)
 	{
-	auto args = zeek::val_list_to_args(vl);
+	auto args = zeek::val_list_to_args(*vl);
 
 	if ( f )
 		conn->EnqueueEvent(f, this, std::move(args));
@@ -811,7 +811,7 @@ void Analyzer::ConnectionEvent(EventHandlerPtr f, val_list* vl)
 
 void Analyzer::ConnectionEvent(EventHandlerPtr f, val_list vl)
 	{
-	auto args = zeek::val_list_to_args(&vl);
+	auto args = zeek::val_list_to_args(vl);
 
 	if ( f )
 		conn->EnqueueEvent(f, this, std::move(args));
@@ -819,7 +819,7 @@ void Analyzer::ConnectionEvent(EventHandlerPtr f, val_list vl)
 
 void Analyzer::ConnectionEventFast(EventHandlerPtr f, val_list vl)
 	{
-	auto args = zeek::val_list_to_args(&vl);
+	auto args = zeek::val_list_to_args(vl);
 	conn->EnqueueEvent(f, this, std::move(args));
 	}
 

src/file_analysis/File.cc

@@ -626,13 +626,13 @@ void File::FileEvent(EventHandlerPtr h)
 
 void File::FileEvent(EventHandlerPtr h, val_list* vl)
 	{
-	FileEvent(h, zeek::val_list_to_args(vl));
+	FileEvent(h, zeek::val_list_to_args(*vl));
 	delete vl;
 	}
 
 void File::FileEvent(EventHandlerPtr h, val_list vl)
 	{
-	FileEvent(h, zeek::val_list_to_args(&vl));
+	FileEvent(h, zeek::val_list_to_args(vl));
 	}
 
 void File::FileEvent(EventHandlerPtr h, zeek::Args args)