- improve parse errors for destructuring spread elements
- `unsafe` for object literals with rest elements
Miscellaneous
- increase mocha unicode surrogate test timeout
- Use AST_Destructuring for lhf assignment patterns
- Use AST_DefaultAssign for default assignments
- Add more checks for lhs expressions
- Add lots of testing
- Cleanup ast (e.g. remove default property)
- Fix#1402 based on a patch from @kzc
- Refine spread allowance in array destructring pattern
- Add destructuring AST tree checker
