ipc/android: Single point of truth for action name.

src/xrt/ipc/android/build.gradle

@@ -12,6 +12,13 @@ android {
         // needed for ASharedMemory, etc.
         minSdkVersion 26
         targetSdkVersion project.sharedTargetSdk
+
+        // Single point of truth for this name.
+        def serviceAction = "org.freedesktop.monado.ipc.CONNECT"
+        manifestPlaceholders = [
+                serviceActionName: serviceAction
+        ]
+        buildConfigField("String", "SERVICE_ACTION", "\"${serviceAction}\"")
     }
 
     buildTypes {

src/xrt/ipc/android/src/main/AndroidManifest.xml

@@ -12,7 +12,7 @@
             android:exported="true"
             android:foregroundServiceType="connectedDevice|mediaPlayback">
             <intent-filter>
-                <action android:name="org.freedesktop.monado.ipc.CONNECT" />
+                <action android:name="${serviceActionName}" />
             </intent-filter>
         </service>
     </application>

src/xrt/ipc/android/src/main/java/org/freedesktop/monado/ipc/Client.java

@@ -152,7 +152,7 @@ public class Client implements ServiceConnection {
             return false;
         }
 
-        Intent intent = new Intent("org.freedesktop.monado.ipc.CONNECT")
+        intent = new Intent(BuildConfig.SERVICE_ACTION)
                 .setPackage(packageName);
 
         context.startForegroundService(intent);