Keep Parcelable CREATOR fields

Change-Id: I64451134a9d11d17307ef4d8ea923df5fe5e37ed

core/proguard_basic_keeps.flags

@@ -49,9 +49,10 @@
 # -keep class * extends android.preference.Preference
 # -keep class * extends android.app.BackupAgent
 
-#-keep class * implements android.os.Parcelable {
-#  public static final android.os.Parcelable$Creator *;
-#}
+# Parcelable CREATORs must be kept for Parcelable functionality
+-keep class * implements android.os.Parcelable {
+  public static final ** CREATOR;
+}
 
 # The support library contains references to newer platform versions.
 # Don't warn about those in case this app is linking against an older