CrashReportDatabase::Initialize(): use the database path

CrashReportDatabase::Initialize(): use the database path.

Rather than accepting the path to the database’s parent directory, this
now accepts the path to the database itself. Using the parent directory
proved cumbersome in practice. When testing crashpad_handler with a
variety of databases, it is useful to be able to specify
--database=/tmp/crashpad_database, --database=/tmp/crashpad_database_2,
etc. The old interface required that these directories be created as a
separate step, and would put the actual database at
/tmp/crashpad_database/Crashpad. This was contrary to the operation of
most tools and interfaces, which would only require that /tmp exist and
would put the database at /tmp/crashpad_database.

TEST=crashpad_client_test
R=rsesek@chromium.org

Committed: https://chromium.googlesource.com/crashpad/crashpad/+/7d5e17cd2e31b52a291e332d3358849e4ba6b6a8

[Mark Mentovai, 2015-03-10 17:50:53]

mark@chromium.org changed reviewers:
+ rsesek@chromium.org, scottmg@chromium.org

[Robert Sesek, 2015-03-10 17:55:17]

LGTM

[Mark Mentovai, 2015-03-10 18:27:59]

Committed patchset #1 (id:1) manually as
7d5e17cd2e31b52a291e332d3358849e4ba6b6a8 (presubmit successful).