Chrome style plugin: enable virtual specifier checks for Gmock objects in //dbus.

Previously, the plugin completely skipped virtual specifier checks on
Gmock objects since it wasn't smart enough to filter out warnings caused
by Gmock macros. In preparation for making the plugin smarter, this CL
fixes existing virtual specifier warnings in //dbus.

This CL was uploaded by git cl split.

[email protected]

Bug: 837148
Change-Id: I2af67226ab01879be81437c2bcf6a2e5e6002987
Reviewed-on: https://chromium-review.googlesource.com/1031184
Reviewed-by: Steven Bennetts <[email protected]>
Commit-Queue: Daniel Cheng <[email protected]>
Cr-Commit-Position: refs/heads/master@{#554265}
3 files changed