Dynamic InCallService switching.

Be able to switch between in-call services UIs.

Created a tree data structure to handle switching between InCallServices
depending on the state of the system.  Tree looks like this:

           CarModeSwitchingConnection
                 |             |
          +------+             +-------+
          |                            |
    CarModeConnection          EmergencyConnection
                                       |
                                       |
                               DefaultDialerConnection

Bug: 24571147
Change-Id: I0999fad4185321d5211172aed2f1d60fe8f5fe3a
diff --git a/testapps/AndroidManifest.xml b/testapps/AndroidManifest.xml
index 3e8fe5b..7327e43 100644
--- a/testapps/AndroidManifest.xml
+++ b/testapps/AndroidManifest.xml
@@ -54,7 +54,7 @@
         <service android:name="com.android.server.telecom.testapps.TestInCallServiceImpl"
                  android:process="com.android.server.telecom.testapps.TestInCallService"
                  android:permission="android.permission.BIND_INCALL_SERVICE" >
-            <meta-data android:name="android.telecom.IN_CALL_SERVICE_CAR_MODE_UI" android:value="true"/>
+            <meta-data android:name="android.telecom.IN_CALL_SERVICE_UI" android:value="true"/>
             <intent-filter>
                 <action android:name="android.telecom.InCallService"/>
             </intent-filter>