Add DvrClient and DvrClientCallback

Test: make libmedia_tv_tuner
Bug: 174095851
Change-Id: I0614a8ca7ca8d177da3f8ad07dbe70c3f57d6f1e
diff --git a/media/jni/tuner/TunerClient.cpp b/media/jni/tuner/TunerClient.cpp
index 2c1735f..bd18c707 100644
--- a/media/jni/tuner/TunerClient.cpp
+++ b/media/jni/tuner/TunerClient.cpp
@@ -40,6 +40,8 @@
     // Connect with Tuner Service.
     ::ndk::SpAIBinder binder(AServiceManager_getService("media.tuner"));
     mTunerService = ITunerService::fromBinder(binder);
+    // TODO: Remove after JNI migration is done.
+    mTunerService = NULL;
     if (mTunerService == NULL) {
         ALOGE("Failed to get tuner service");
     }