Comment 3 for bug 883879

Attached is a patch that fixes the shadowing of the property (writes to user-stylesheet-uri wrap the value, reads get the value webkit should read; this seems to be the only way for this to work properly) and implements a more efficient hash-based method of generating strings that only base64s individual chunks upon their addition. It also moves the "import" to the beginning of the generated CSS because this is required for import rules to apply.

This approach does not do anything with lists, but that still might be worthwhile to determine if it's faster or not.