Don't map null arguments to any parameters.

EA-98555, EA-98663 Fixed.

python/src/com/jetbrains/python/psi/impl/PyCallExpressionHelper.java

@@ -689,7 +689,9 @@ public class PyCallExpressionHelper {
         final String parameterName = namedParameter.getName();
         if (namedParameter.isPositionalContainer()) {
           for (PyExpression argument : allPositionalArguments) {
-            mappedParameters.put(argument, namedParameter);
+            if (argument != null) {
+              mappedParameters.put(argument, namedParameter);
+            }
           }
           if (variadicPositionalArguments.size() == 1) {
             mappedParameters.put(variadicPositionalArguments.get(0), namedParameter);

python/testData/inspections/PyTypeCheckerInspection/NullArgumentMappedToPositionalParameter.py

@@ -0,0 +1,6 @@
+class Kvas:
+    def __getitem__(self, *item):
+        pass
+
+
+Kvas()[<error descr="expression expected">]</error>

python/testSrc/com/jetbrains/python/inspections/PyTypeCheckerInspectionTest.java

@@ -371,4 +371,9 @@ public class PyTypeCheckerInspectionTest extends PyTestCase {
   public void testIteratingOverListAfterIfNot() {
     doTest();
   }
+
+  // EA-98555, EA-98663
+  public void testNullArgumentMappedToPositionalParameter() {
+    doTest();
+  }
 }