Merge pull request #1324 from aschackmull/java/switchexpr-nullness

Java: Add SwitchExpr to Nullness::dereference.

Author: yh-semmle

java/ql/src/semmle/code/java/dataflow/Nullness.qll

@@ -104,6 +104,8 @@ predicate dereference(Expr e) {
   or
   exists(SwitchStmt switch | switch.getExpr() = e)
   or
+  exists(SwitchExpr switch | switch.getExpr() = e)
+  or
   exists(FieldAccess fa, Field f | fa.getQualifier() = e and fa.getField() = f and not f.isStatic())
   or
   exists(MethodAccess ma, Method m |