Remove build step that escapes unicode in autofill_regex_constants.cc

Remove build step that escapes unicode in autofill_regex_constants.cc

Just put the unicode directly into the .cc file. I'm not sure when this
became possible, but we have tests that put unicode directly in string
literals without escaping.

BUG=478334
Committed: https://crrev.com/ef2d6eb985b01fe0df168aa6c4cc8d8d8eac73b2
Cr-Commit-Position: refs/heads/master@{#325918}

[Evan Stade, 2015-04-20 17:39:33]

estade@chromium.org changed reviewers:
+ brettw@chromium.org

[brettw, 2015-04-20 19:26:32]

lgtm

[Evan Stade, 2015-04-20 20:37:46]

The CQ bit was checked by estade@chromium.org

[commit-bot: I haz the power, 2015-04-20 20:38:10]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1090373002/60001

[commit-bot: I haz the power, 2015-04-20 22:05:24]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2015-04-20 22:06:18]

Patchset 4 (id:??) landed as
https://crrev.com/ef2d6eb985b01fe0df168aa6c4cc8d8d8eac73b2
Cr-Commit-Position: refs/heads/master@{#325918}