Migrate WallpaperStatsLog.java to genrule inside Android.bp

Test: build success, logging verified
Bug: 147824671

Change-Id: I9abd57fa3a791167763109053dff44000d5bdcf0
diff --git a/Android.mk b/Android.mk
index 81a2976..a098ee2 100644
--- a/Android.mk
+++ b/Android.mk
@@ -26,7 +26,7 @@
 LOCAL_MODULE_TAGS := optional
 
 LOCAL_STATIC_ANDROID_LIBRARIES := WallpaperPicker2CommonDepsLib
-LOCAL_STATIC_JAVA_LIBRARIES := styleprotosnano
+LOCAL_STATIC_JAVA_LIBRARIES := styleprotosnano SystemUI-statsd
 LOCAL_PROGUARD_ENABLED := disabled
 LOCAL_SDK_VERSION := system_current