Allow spaces within media query features

[nacin]

This (note whitespace around max-width: 710px) should be valid:

@media screen and ( max-width: 710px ) {}

Currently the whole line errors out:

[L1:C20]
>> ERROR: Expected IDENT at line 1, col 20. This rule looks for recoverable syntax errors. (errors) Browsers: All
[L1:C32]
>> ERROR: Expected LBRACE at line 1, col 32. This rule looks for recoverable syntax errors. (errors) Browsers: All
[L1:C32]
>> ERROR: Unexpected token '710px' at line 1, col 32. This rule looks for recoverable syntax errors. (errors) Browsers: All
[L1:C38]
>> ERROR: Unexpected token ')' at line 1, col 38. This rule looks for recoverable syntax errors. (errors) Browsers: All
[L1:C40]
>> ERROR: Unexpected token '{' at line 1, col 40. This rule looks for recoverable syntax errors. (errors) Browsers: All
[L1:C41]
>> ERROR: Unexpected token '}' at line 1, col 41. This rule looks for recoverable syntax errors. (errors) Browsers: All

This PR fixes CSSLint/csslint#541 with a simple this._readWhitespace(); call, and includes tests.

[stubbornella]

Is there any way to assert something more meaningful? Could you test error count?

[stubbornella]

Looks good overall. Just a couple questions about the tests.

[nacin]

@stubbornella Sure, these assertions are certainly suspect. Please note this was me just following the existing pattern in the file. I added two Assert.isTrue(true); — the related tests already had 15 just like it, for the same purposes, dating to 2011. (21c91f8)

So, yes, all of these should probably be refactored, but probably in a separate PR, and probably by someone with a bit more knowledge of parser-lib. 😅