debugd: Use cromo and ModemManager DBus service constants.

BUG=None
CQ-DEPEND=CL:199602
CQ-DEPEND=CL:199609
TEST=Tested the following:
1. Build and run unit tests.
2. Run the command below in a root shell:

   dbus-send --system --print-reply --dest=org.chromium.debugd \
       /org/chromium/debugd org.chromium.debugd.SetDebugMode \
       string:cellular

   dbus-send --system --print-reply --dest=org.chromium.debugd \
       /org/chromium/debugd org.chromium.debugd.GetModemStatus

Change-Id: I505d38c639a70652a6ed59ea9f1bba1c058c37c8
Reviewed-on: https://chromium-review.googlesource.com/199666
Reviewed-by: Thieu Le <thieule@chromium.org>
Reviewed-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
2 files changed
tree: 65032c55761d704a2e7ed665f87480d9648bd60e
  1. .gitignore
  2. OWNERS
  3. README
  4. debugd.gyp
  5. doc/
  6. share/
  7. src/