Fix saveLayer() with a pixel-moving filter vs SkBBoxHierarchyRecord / SkRecordDraw

src/core/SkRecordDraw.cpp

Index: src/core/SkRecordDraw.cpp
diff --git a/src/core/SkRecordDraw.cpp b/src/core/SkRecordDraw.cpp
index c9e029b8db67f11a59c9844a3128f5042931dedf..4ca398574e76185dadfeca61a9e2463bfbf68307 100644
--- a/src/core/SkRecordDraw.cpp
+++ b/src/core/SkRecordDraw.cpp
@@ -189,19 +189,29 @@ private:
         this->pushControl();
     }
 
+    static bool PaintMayAffectTransparentBlack(const SkPaint* paint) {
+        // FIXME: this is very conservative
+        return paint && (paint->getImageFilter() || paint->getColorFilter());
+    }
+
     SkIRect popSaveBlock() {
         // We're done the Save block.  Apply the block's bounds to all control ops inside it.
         SaveBounds sb;
         fSaveStack.pop(&sb);
+
+        // If the paint affects transparent black, we can't trust any of our calculated bounds.
+        const SkIRect& bounds =
+            PaintMayAffectTransparentBlack(sb.paint) ? fCurrentClipBounds : sb.bounds;
+
         while (sb.controlOps --> 0) {
-            this->popControl(sb.bounds);
+            this->popControl(bounds);
         }
 
         // This whole Save block may be part another Save block.
-        this->updateSaveBounds(sb.bounds);
+        this->updateSaveBounds(bounds);
 
         // If called from a real Restore (not a phony one for balance), it'll need the bounds.
-        return sb.bounds;
+        return bounds;
     }
 
     void pushControl() {