Issue 6841 part 2: Use inIDOMUtils.getCSSValuesForProperty for auto-completing property values

https://code.google.com/p/fbug/issues/detail?id=6841
Issue 6841 part 3: Kill old data tables
Auto-complete "initial" and "unset" (related to issue 6841)
Issue 6841 part 4: some follow-ups
Fix a test after issue 6841

Auto-completions are now sorted alphabetically
Merge branch 'css-api-completion' into jsd2