[Javascript] Fix SWIG_exception() macro (#792)

Fix SWIG_exception() macro to return from the current function.
Fixes #789, reported by Julien Dutriaux.

Lib/javascript/jsc/javascriptcode.swg

@@ -32,6 +32,7 @@ static JSObjectRef $jswrapper(JSContextRef context, JSObjectRef ctorObject,
     size_t argc, const JSValueRef argv[], JSValueRef* exception)
 {
     SWIG_exception(SWIG_ERROR, "Class $jsname can not be instantiated");
+fail:
     return 0;
 }
 %}

Lib/javascript/jsc/javascripthelpers.swg

@@ -53,7 +53,7 @@ SWIGINTERN bool JS_veto_set_variable(JSContextRef context, JSObjectRef thisObjec
     } else {
       SWIG_exception(SWIG_ERROR, msg);
     }
-    
+fail:    
     return false;
 }
 

Lib/javascript/jsc/javascriptrun.swg

@@ -4,7 +4,7 @@
  * ---------------------------------------------------------------------------*/
 
 #define SWIG_Error(code, msg)     SWIG_JSC_exception(context, exception, code, msg)
-#define SWIG_exception(code, msg) SWIG_JSC_exception(context, exception, code, msg)
+#define SWIG_exception(code, msg) do { SWIG_JSC_exception(context, exception, code, msg); SWIG_fail; } while (0)
 #define SWIG_fail                 goto fail
 
 SWIGRUNTIME void SWIG_Javascript_Raise(JSContextRef context, JSValueRef *exception, const char* type) {