Fix ExoPlayer's demo app gradle build

Broken by https://github.com/google/ExoPlayer/commit/399aa706a7e570e8ed7ca93b54beaae6ee3dac91.

PiperOrigin-RevId: 241770676

demos/main/src/main/java/com/google/android/exoplayer2/demo/TrackSelectionDialog.java

@@ -20,7 +20,7 @@ import android.content.DialogInterface;
 import android.content.res.Resources;
 import android.content.res.Resources;
 import android.os.Bundle;
 import android.os.Bundle;
 import androidx.annotation.Nullable;
 import androidx.annotation.Nullable;
-import android.support.design.tabs.TabLayout;
+import com.google.android.material.tabs.TabLayout;
 import androidx.fragment.app.DialogFragment;
 import androidx.fragment.app.DialogFragment;
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentManager;