Moved some duplicate password_manager constants into shared code

chrome/browser/password_manager had a couple of trivial constants
and helper functiosn defined multiple times.

In jumbo builds many cc files compile in the same translation
unit and then they share the same anonymous namespace. With multiple
definitions of a constant, with the same name, you get compilation
errors.

In preparation for jumbo in chrome/browser, this patch moves the
constants into the shared file and it removes a random
constant for "". The code doesn't normally use constants
for "".

Bug: 746957
Change-Id: I069e6c9e18b23ce4597c9f23aee829f85e2d17a1
Reviewed-on: https://chromium-review.googlesource.com/897814
Reviewed-by: Vadym Doroshenko <dvadym@chromium.org>
Commit-Queue: Daniel Bratell <bratell@opera.com>
Cr-Commit-Position: refs/heads/master@{#534438}
5 files changed