per clause tests for stack map generation

tests/bugs170/language/PerCflow.java

+aspect PerCflow percflow(execution(* Bar.*(..))) {
+}
+
+class Bar {
+  void m() { 
+    n();
+  }
+  void n() { 
+  }
+}

tests/bugs170/language/PerTarget.java

+aspect PerTarget pertarget(this(PerTarget)) { }

tests/bugs170/language/PerThis.java

+aspect PerThis perthis(this(PerThis)) { }

tests/bugs170/language/PerTypeWithin.java

+aspect PerTypeWithin pertypewithin(PerTypeWithin) { }