Move isolatable bluetooth code to SettingsLib

Move the non-ui bluetooth control/tracking code to SettingsLib so
that it can be shared with others.

Mostly just move classes to frameworks/base/packages/SettingsLib,
however a few things had to move around.
 - Dock handling had to move back to code still in settings
 - Local preference related code had to be moved back to settings
 - Added an error flow from SettingsLib to Settings

Depends on I69fd888362c6dbb325f6113b32c4b15cc6a23a41
Bug: 19180466
Change-Id: Ie57fe26a27bbb0adc2ef69e042a05c7290c6a52a

src/com/android/settings/bluetooth/BluetoothEnabler.java

@@ -31,6 +31,8 @@ import com.android.settings.R;
 import com.android.settings.search.Index;
 import com.android.settings.widget.SwitchBar;
 import com.android.settingslib.WirelessUtils;
+import com.android.settingslib.bluetooth.LocalBluetoothAdapter;
+import com.android.settingslib.bluetooth.LocalBluetoothManager;
 
 /**
  * BluetoothEnabler is a helper to manage the Bluetooth on/off checkbox
@@ -77,7 +79,7 @@ public final class BluetoothEnabler implements SwitchBar.OnSwitchChangeListener
         mSwitch = switchBar.getSwitch();
         mValidListener = false;
 
-        LocalBluetoothManager manager = LocalBluetoothManager.getInstance(context);
+        LocalBluetoothManager manager = Utils.getLocalBtManager(context);
         if (manager == null) {
             // Bluetooth is not supported
             mLocalAdapter = null;