google-breakpad: Remove legacy files and core_dumper target.

The Chromium OS changes to google-breakpad have been upstreamed (r905).
This CL modifies the google-breakpad ebuild to remove the core_dumper
target and other legacy files.

BUG=chromium-os:22042
TEST=Verified the following:
1. emerge google-breadpad for x86-generic, arm-generic and amd64-generic
2. cros_run_unit_tests -p google-breakpad for x86-generic, amd64-generic
3. Run the following autotest tests on a Cr48:
   - logging_CrashSender
   - logging_UserCrash

Change-Id: Icf8644c8080d1de83e00c289296de8c3a9eb0d53
Reviewed-on: https://gerrit.chromium.org/gerrit/14544
Reviewed-by: Michael Krebs <mkrebs@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
Commit-Ready: Ben Chan <benchan@chromium.org>
11 files changed