diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/debug/Debugger-debuggees-09.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/debug/Debugger-debuggees-09.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,22 @@
+// |jit-test| debug
+// If hasDebuggee(x) is false, removeDebuggee(x) does nothing.
+
+var dbg = new Debugger;
+
+function check(obj) {
+    // If obj is something we could never debug, hasDebuggee(obj) is false.
+    assertEq(dbg.hasDebuggee(obj), false);
+
+    // If hasDebuggee(x) is false, removeDebuggee(x) does nothing.
+    assertEq(dbg.removeDebuggee(obj), undefined);
+}
+
+// global objects which happen not to be debuggees at the moment
+var g1 = newGlobal('same-compartment');
+check(g1);
+
+// objects in a compartment that is already debugging us
+var g2 = newGlobal();
+g2.parent = this;
+g2.eval("var dbg = new Debugger(parent);");
+check(g2);