dbus: Check ObjectPath's validity in objects' ctors

BUG=767024
TEST=dbus_unittests && chromeos_unittests

Change-Id: I5561618b0a9f9cfb3bb23d96992811301e523b43
Reviewed-on: https://chromium-review.googlesource.com/678355
Commit-Queue: Ryo Hashimoto <hashimoto@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Cr-Commit-Position: refs/heads/master@{#503998}

CrOS-Libchrome-Original-Commit: c089a029490f36c9d5be00030eff8262b1736daa
5 files changed
tree: d6f0cdcd3c4cd8e37b3ec9af2eca03cea6f71e99
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/