Add some debugging code to track down a BatteryStatusManagerLinux crash.

BUG=746146

Change-Id: Ib18b966545eb9034736698206174b9e3b73a88d7
Reviewed-on: https://chromium-review.googlesource.com/578573Reviewed-by: Tim Volodine <timvolodine@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#488393}

services/device/battery/battery_status_manager_linux.cc

@@ -373,6 +373,9 @@ class BatteryStatusManagerLinux::BatteryStatusNotificationThread
   }
 
   bool IsDaemonVersionBelow_0_99() {
+    // TODO(thestig): Fix https://crbug.com/746146 and remove these CHECKs.
+    CHECK(upower_);
+    CHECK(upower_->properties());
     base::Version daemon_version = upower_->properties()->daemon_version();
     return daemon_version.IsValid() &&
            daemon_version.CompareTo(base::Version("0.99")) < 0;