1. Location names with more than one underscores (e.g. Ho_Chi_Minh)
   didn't work because of the way capturing works with repeated patterns
   in RE. It's now supported by changing the RE to capture the whole string
   and splitting on '_' in the next step.

2. Adds support for location names with a hyphen

3. Adds support for timezone ids with three parts (e.g.
   American/Argentina/Buenos_Aires)

4. Adds special handling of 'au', 'es' and 'of' in zone ids. They need to be kept in lowercase. (see the full list at https://en.wikipedia.org/wiki/List_of_tz_database_time_zones )

5. Adds regression tests for all the above and make the existing tests
   more robust against future ICU changes. ICU canonicalizes zone names to
   deprecated names, but it may change. (
   http://bugs.icu-project.org/trac/ticket/12044 )

BUG=364374
LOG=Y

Review URL: https://codereview.chromium.org/1529363005

Cr-Commit-Position: refs/heads/master@{#33097}