Fix up my refactoring mistake in toThrowError

strengthen the associated tests to protect against it in the future

src/core/matchers/toThrowError.js

@@ -124,14 +124,14 @@ getJasmineRequireObj().toThrowError = function() {
         }
 
         function checkForAnErrorType(type) {
-          if (typeof expected == "function") {
+          if (typeof type !== "function") {
             return false;
           }
 
           var Surrogate = function() {};
           Surrogate.prototype = type.prototype;
           return (new Surrogate()) instanceof Error;
-        };
+        }
       }
     };
   }