Revert "[Bluetooth] Enable by default peripheral battery UI indication."

This reverts commit 4e060f87.

Reason for revert: Breaks connection with LE device, for example LE keyboard.

Original change's description:
> [Bluetooth] Enable by default peripheral battery UI indication.
> 
> Bug: 785758
> Change-Id: I35f3270d0b61b8f0e3e3bde6d64f5b1c54f1a254
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1752913
> Commit-Queue: Ryan Hansberry <hansberry@chromium.org>
> Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
> Auto-Submit: Ryan Hansberry <hansberry@chromium.org>
> Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#686638}

TBR=khorimoto@chromium.org,hansberry@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 785758
Change-Id: Ief7a8ed1a5bcd925b8e94b4249f52aec89687aeb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1778918Reviewed-by: Sonny Sasaka <sonnysasaka@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Sonny Sasaka <sonnysasaka@chromium.org>
Cr-Commit-Position: refs/heads/master@{#692183}

chromeos/constants/chromeos_features.cc

@@ -159,7 +159,7 @@ const base::Feature kReleaseNotes{"ReleaseNotes",
 // Enables or disables showing the battery level in the System Tray and Settings
 // UI for supported Bluetooth Devices.
 const base::Feature kShowBluetoothDeviceBattery{
-    "ShowBluetoothDeviceBattery", base::FEATURE_ENABLED_BY_DEFAULT};
+    "ShowBluetoothDeviceBattery", base::FEATURE_DISABLED_BY_DEFAULT};
 
 // Shows the Play Store icon in Demo Mode.
 const base::Feature kShowPlayInDemoMode{"ShowPlayInDemoMode",