fix bugs with getter/setter (#1926)

- `reduce_vars`
- `side_effects`
- property access for object
- `AST_SymbolAccessor` as key names

enhance `test/ufuzz.js`
- add object getter & setter
  - property assignment to setter
  - avoid infinite recursion in setter
- fix & adjust assignment operators
  - 50% `=`
  - 25% `+=`
  - 2.5% each for the rest
- avoid "Invalid array length"
- fix `console.log()`
  - bypass getter
  - curb recursive reference
- deprecate `-E`, always report runtime errors

lib/parse.js

@@ -1320,10 +1320,15 @@ function parse($TEXT, options) {
             var type = start.type;
             var name = as_property_name();
             if (type == "name" && !is("punc", ":")) {
+                var key = new AST_SymbolAccessor({
+                    start: S.token,
+                    name: as_property_name(),
+                    end: prev()
+                });
                 if (name == "get") {
                     a.push(new AST_ObjectGetter({
                         start : start,
-                        key   : as_atom_node(),
+                        key   : key,
                         value : create_accessor(),
                         end   : prev()
                     }));
@@ -1332,7 +1337,7 @@ function parse($TEXT, options) {
                 if (name == "set") {
                     a.push(new AST_ObjectSetter({
                         start : start,
-                        key   : as_atom_node(),
+                        key   : key,
                         value : create_accessor(),
                         end   : prev()
                     }));