Don't invalidate entire recipient cache when contact data changes

src/org/thoughtcrime/securesms/recipients/Recipient.java

@@ -24,6 +24,8 @@ import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.util.Log;
 
+import com.annimon.stream.Stream;
+
 import org.thoughtcrime.securesms.color.MaterialColor;
 import org.thoughtcrime.securesms.contacts.avatars.ContactColors;
 import org.thoughtcrime.securesms.contacts.avatars.ContactPhoto;
@@ -40,6 +42,7 @@ import org.thoughtcrime.securesms.util.ListenableFutureTask;
 import org.thoughtcrime.securesms.util.Util;
 import org.whispersystems.libsignal.util.guava.Optional;
 
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.LinkedList;