shill: Replace VLOG with SLOG.

This CL replaces all uses of VLOG(level) with SLOG(scope, level) with
the same verbose level and an appropriate scope for each affected
logging statement.

BUG=chromium-os:29641
TEST=Build and run unit tests. Test scope logging with ff_debug.

Change-Id: Ifdcf1faa2a309bcbd9ee369a66179ce9c7f1ad19
Reviewed-on: https://gerrit.chromium.org/gerrit/20629
Commit-Ready: Ben Chan <benchan@chromium.org>
Reviewed-by: Ben Chan <benchan@chromium.org>
Tested-by: Ben Chan <benchan@chromium.org>
diff --git a/power_manager_proxy.cc b/power_manager_proxy.cc
index 2531e15..c256d33 100644
--- a/power_manager_proxy.cc
+++ b/power_manager_proxy.cc
@@ -7,6 +7,8 @@
 #include <base/logging.h>
 #include <chromeos/dbus/service_constants.h>
 
+#include "shill/scope_logger.h"
+
 using std::string;
 
 namespace shill {
@@ -32,13 +34,13 @@
 
 // TODO(quiche): make this signal work again. crosbug.com/27475
 void PowerManagerProxy::Proxy::SuspendDelay(const uint32_t &sequence_number) {
-  VLOG(2) << __func__ << "(" << sequence_number << ")";
+  SLOG(Power, 2) << __func__ << "(" << sequence_number << ")";
   delegate_->OnSuspendDelay(sequence_number);
 }
 
 void PowerManagerProxy::Proxy::PowerStateChanged(
     const string &new_power_state) {
-  VLOG(2) << __func__ << "(" << new_power_state << ")";
+  SLOG(Power, 2) << __func__ << "(" << new_power_state << ")";
 
   PowerManagerProxyDelegate::SuspendState suspend_state;
   if (new_power_state == "on") {