Java/Python: Fix some potential performance problems due to transitive deltas.

java/ql/lib/semmle/code/java/frameworks/Rmi.qll

@@ -14,5 +14,5 @@ class RemoteCallableMethod extends Method {
 private predicate remoteCallableMethod(Method method) {
   method.getDeclaringType().getASupertype() instanceof TypeRemote
   or
-  exists(Method meth | remoteCallableMethod(meth) and method.getAnOverride() = meth)
+  exists(Method meth | remoteCallableMethod(meth) and method.overrides(meth))
 }

python/ql/lib/semmle/python/Exprs.qll

@@ -17,7 +17,7 @@ class Expr extends Expr_, AstNode {
    * Whether this expression defines variable `v`
    * If doing dataflow, then consider using SsaVariable.getDefinition() for more precision.
    */
-  predicate defines(Variable v) { this.getASubExpression+().defines(v) }
+  predicate defines(Variable v) { this.getASubExpression().defines(v) }
 
   /** Whether this expression may have a side effect (as determined purely from its syntax) */
   predicate hasSideEffects() {

python/ql/lib/semmle/python/pointsto/PointsTo.qll

@@ -300,7 +300,7 @@ module PointsToInternal {
     ssa_definition_points_to(var.getDefinition(), context, value, origin)
     or
     exists(EssaVariable prev |
-      ssaShortCut+(prev, var) and
+      ssaShortCut(prev, var) and
       variablePointsTo(prev, context, value, origin)
     )
   }