Deal with trailing commas errors

We found some trailing commas errors when compiling the packed code with Closure Compiler.

The errors can be reproduced by packing the code and compile with the online compiler:
```
python3 -t amd -n
```
http://closure-compiler.appspot.com/home

Full error log is:
```
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 2582 character 0
begin: '/', end: '/[a-z]*',
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 2585 character 0
begin: '%r\\[', end: '\\][a-z]*',
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 3251 character 0
{
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 3906 character 0
begin: '[\'`]\\(', end: '\\)',
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 3909 character 0
begin: '\\(quote ', end: '\\)',
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 4789 character 0
className: 'variable',
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 5000 character 0
keyword:
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 5898 character 0
className: 'function',
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 5902 character 0
hljs.UNDERSCORE_TITLE_MODE,
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 6329 character 0
hljs.inherit(hljs.QUOTE_STRING_MODE, {contains: [{begin: '""'}]}),
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 6334 character 0
{
^
JSC_TRAILING_COMMA: Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option. at line 6438 character 0
keyword: //ex command
^
```