Refactor safe-browsing build-config definitions.
Centralize the configuration and break things down into individual sub-systems to enable, rather than referring to feature bundles.
I will in a later CL add safe_browsing==3 for enabling XLB on Android, which will define SAFE_BROWSING_DB_REMOTE. When launched, this will replace mode 2.
SAFE_BROWSING_SERVICE - enable the browser to talk to the server.
SAFE_BROWSING_DB_LOCAL - maintain local database(s) synced from the server.
SAFE_BROWSING_DB_REMOTE - talk via API to an external DB (i.e. XLB).
SAFE_BROWSING_CSD - client-side phishing detection support.
This is nearly a copy of shess@'s 8-month-old
https://codereview.chromium.org/397853002/ which was LGTMed. Diffs: Mostly merge conflicts, a rename, and few files added
BUG=394379,474608
Review URL: https://codereview.chromium.org/1081403002
Cr-Commit-Position: refs/heads/master@{#325775}
35 files changed
