b/2296110 Dialog for setting up dock audio.

Reimplemented as a Foreground Service just so it can get on top of the Car Dock App.
Added debounce mechanism to not disconnect immediately after getting a undock event.
Each dock now has its own "Remember setting".
Remember Settings is on by default

Change-Id: I80790bdb7c831e2a642365b92433012191aa70c1
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 974950d..f3f33ac 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -489,20 +489,14 @@
         </activity>
 
         <receiver
-            android:name=".bluetooth.DockAudioStateChangeReceiver"
-            >
+            android:name=".bluetooth.DockEventReceiver">
             <intent-filter>
                 <action android:name="android.intent.action.DOCK_EVENT" />
                 <category android:name="android.intent.category.DEFAULT" />
             </intent-filter>
         </receiver>
 
-        <activity android:name=".bluetooth.DockSettingsActivity"
-                  android:label="@string/bluetooth_dock_settings"
-                  android:launchMode="singleTask"
-                  android:excludeFromRecents="true"
-                  android:theme="@*android:style/Theme.Dialog.Alert">
-        </activity>
+        <service android:name=".bluetooth.DockService" />
 
         <activity android:name=".bluetooth.RequestPermissionActivity"
                   android:label="@string/bluetooth_permission_request"