libweave: Remove unused dbus references

Removed few unused forward declarations, friend classes and includes.

BUG=brillo:1251
TEST='FEATURES=test emerge-gizmo buffet'

Change-Id: Ibe3df462e0ed47e85937a778bdc7c6f46a65bd6a
Reviewed-on: https://chromium-review.googlesource.com/290102
Reviewed-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Vitaly Buka <vitalybuka@chromium.org>
Commit-Queue: Vitaly Buka <vitalybuka@chromium.org>
Tested-by: Vitaly Buka <vitalybuka@chromium.org>

libweave/src/commands/command_instance.h

diff --git a/libweave/src/commands/command_instance.h b/libweave/src/commands/command_instance.h
index ee70065..1b30d53 100644
--- a/libweave/src/commands/command_instance.h
+++ b/libweave/src/commands/command_instance.h
@@ -115,8 +115,6 @@
   // The queue owns the command instance, so it outlives this object.
   CommandQueue* queue_ = nullptr;
 
-  friend class DBusCommandDispacherTest;
-  friend class DBusCommandProxyTest;
   DISALLOW_COPY_AND_ASSIGN(CommandInstance);
 };
 

libweave/src/commands/command_manager.cc

diff --git a/libweave/src/commands/command_manager.cc b/libweave/src/commands/command_manager.cc
index 3704803..0cb36b0 100644
--- a/libweave/src/commands/command_manager.cc
+++ b/libweave/src/commands/command_manager.cc
@@ -6,7 +6,6 @@
 
 #include <base/files/file_enumerator.h>
 #include <base/values.h>
-#include <chromeos/dbus/exported_object_manager.h>
 #include <chromeos/errors/error.h>
 
 #include "libweave/src/commands/schema_constants.h"

libweave/src/commands/command_queue.h

diff --git a/libweave/src/commands/command_queue.h b/libweave/src/commands/command_queue.h
index 1fbc294..f279c38 100644
--- a/libweave/src/commands/command_queue.h
+++ b/libweave/src/commands/command_queue.h
@@ -52,7 +52,6 @@
 
  private:
   friend class CommandQueueTest;
-  friend class DBusCommandDispacherTest;
 
   // Removes a command identified by |id| from the queue.
   bool Remove(const std::string& id);