python: make ArgumentNode publicly usable

- add `getCall`

python/ql/test/experimental/dataflow/TestUtil/MaximalFlowTest.qll

@@ -35,7 +35,7 @@ class MaximalFlowsConfig extends DataFlow::Configuration {
   override predicate isSink(DataFlow::Node node) {
     exists(node.getLocation().getFile().getRelativePath()) and
     not any(CallNode c).getArg(_) = node.asCfgNode() and
-    not node instanceof DataFlow::ArgumentSourceNode and
+    not node instanceof DataFlow::ArgumentNode and
     not node.asCfgNode().(NameNode).getId().matches("SINK%") and
     not exists(DataFlow::Node succ | DataFlow::localFlowStep(node, succ))
   }

python/ql/test/experimental/dataflow/TestUtil/RoutingTest.qll

@@ -43,7 +43,7 @@ abstract class RoutingTest extends InlineExpectationsTest {
   }
 
   pragma[inline]
-  private string fromFunc(DataFlow::ArgumentSourceNode fromNode) {
+  private string fromFunc(DataFlow::ArgumentNode fromNode) {
     result = fromNode.getCall().getNode().(CallNode).getFunction().getNode().(Name).getId()
   }
 

python/ql/test/experimental/dataflow/callGraphConfig.qll

@@ -11,7 +11,7 @@ class CallGraphConfig extends DataFlow::Configuration {
   override predicate isSource(DataFlow::Node node) {
     node instanceof DataFlowPrivate::ReturnNode
     or
-    node instanceof DataFlow::ArgumentSourceNode
+    node instanceof DataFlow::ArgumentNode
   }
 
   override predicate isSink(DataFlow::Node node) {

python/ql/test/experimental/dataflow/coverage/classesCallGraph.ql

@@ -11,7 +11,7 @@ class CallGraphConfig extends DataFlow::Configuration {
     node instanceof DataFlowPrivate::ReturnNode
     or
     // These sources should allow for the non-standard call syntax
-    node instanceof DataFlow::ArgumentSourceNode
+    node instanceof DataFlow::ArgumentNode
   }
 
   override predicate isSink(DataFlow::Node node) {