Java: bugfix

Author: aschackmull

java/ql/lib/semmle/code/java/dataflow/internal/DataFlowPrivate.qll

@@ -150,7 +150,11 @@ predicate readStep(Node node1, Content f, Node node2) {
  * in `x.f = newValue`.
  */
 predicate clearsContent(Node n, Content c) {
-  exists(FieldAccess fa | instanceFieldAssign(_, fa) and n = getFieldQualifier(fa))
+  exists(FieldAccess fa |
+    instanceFieldAssign(_, fa) and
+    n = getFieldQualifier(fa) and
+    c.(FieldContent).getField() = fa.getField()
+  )
   or
   FlowSummaryImpl::Private::Steps::summaryClearsContent(n, c)
 }