remove legacy filter-flags, and store FilterLevel directly

src/pipe/SkGPipeWrite.cpp

Index: src/pipe/SkGPipeWrite.cpp
diff --git a/src/pipe/SkGPipeWrite.cpp b/src/pipe/SkGPipeWrite.cpp
index 17695ae63f6f082206ef071e6f6316bd21f88096..6964dc140f75402ecacf412efd70d061677be125 100644
--- a/src/pipe/SkGPipeWrite.cpp
+++ b/src/pipe/SkGPipeWrite.cpp
@@ -1052,6 +1052,10 @@ void SkGPipeCanvas::writePaint(const SkPaint& paint) {
         *ptr++ = paint.getColor();
         base.setColor(paint.getColor());
     }
+    if (base.getFilterLevel() != paint.getFilterLevel()) {
+        *ptr++ = PaintOp_packOpData(kFilterLevel_PaintOp, paint.getFilterLevel());
+        base.setFilterLevel(paint.getFilterLevel());
+    }
     if (base.getStyle() != paint.getStyle()) {
         *ptr++ = PaintOp_packOpData(kStyle_PaintOp, paint.getStyle());
         base.setStyle(paint.getStyle());