See the comments for an explanation of how properties are stored.
The trie structure is designed to scale better than the previous
array-based implementation. Searching an array with n properties
required average O(n) string compares of the entire key; searching the
trie requires average O(log n) string compares of each token (substrings
between '.' characters).
Change-Id: Ic28b3c5246004a3c502eb02d6e1c9b512884d872
Signed-off-by: Greg Hackmann <ghackmann@google.com>
4482d85139