CSS plugin does not maintain relative URLs

[eoneill]

When using the CSS plugin, Inject should adjust non-qualified URLs to make sure they're pointing to the correct path.

e.g. if my CSS file contains a relative image page, the Injected CSS file should respect the relative path of the origin CSS file, not the page it's being injected into.

// where:
// `resolvedPath` is the path to the CSS module we XHR
//    e.g. `http://www.licdn.com/scds/concat/common/css?f=scss/some/file`
// `content` is the body of the CSS module

// matches non-qualified `url()` notations within the content
//  includes AlphaImageLoader(src="...")
//  excludes any fully qualified URLs, scheme-less URLs, or URIs with valid protocols
var rNonQualifiedUrl = /((?:url\s*\(|AlphaImageLoader\s*\(\s*src\s*=)\s*['"]?(?!\/\/|[a-z]+\:))(.)/igm;

// matches up to the pathname of the URL
var rBasePath = /(?:^(?:https?\:)?\/\/[^\/\?\#]+)/i;

// matches any extraneous query/hash info that isn't relevant to URL path resolution
var rQueryOrHash = /\/?[\?\#].*/;

// strip off any query or hash on the file path string
var basePath = resolvedPath.replace(rQueryOrHash, '');
// the fully qualified path to the host (excluding any pathname, hash, query)
var hostPath = rBasePath.exec(resolvedPath)[0];

// adjust any non-qualified URLs in the content
content.replace(rNonQualifiedUrl, function() {
  var result = arguments[1];
  if (arguments[2][0] === '/') {
    result += hostPath + arguments[2];
  }
  else {
    result += basePath + '/' + arguments[2]
  }
  return result;
});

some expectations, assuming the resolvedPath to the CSS module was: http://cdn.server.com/path/to/my.css

url(/images/some/image.png)
 -> url(http://cdn.server.com/images/some/image.png)

url("../../relative.png")
 -> url("http://cdn.server.com/path/to/my.css/../../relative.png")

url('http://www.cdn.com/image.png')
 -> url('http://www.cdn.com/image.png') // untouched

url(data:image/png;base64,abcdEFG)
 -> url(data:image/png;base64,abcdEFG) // untouched

progid:DXImageTransform.Microsoft.AlphaImageLoader(src='/path/to/image.png',sizingMethod='scale')
 -> progid:DXImageTransform.Microsoft.AlphaImageLoader(src='http://cdn.server.com/path/to/image.png',sizingMethod='scale')