web-animations is weird because it can be referred to either as
'web-animations' or 'web-animations/web-animations-js'. Manually
entering it as the former confuses bower2buck when it's referred to
elsewhere as the latter.
Run bower2buck to normalize the current contents.
Band-aid the situation for now, and jot down some of my ideas for
fixing when I find the time.
Change-Id: I64ae3c376df7b83008462c663de4a3998749c365