Fix for empty saveLayer() with a filter which affects transparent black.

src/core/SkPictureRecord.cpp

Index: src/core/SkPictureRecord.cpp
diff --git a/src/core/SkPictureRecord.cpp b/src/core/SkPictureRecord.cpp
index f6da2f27932698002c1081b1277235d85dedd2f3..4a5aff2d722d7a66c66eac6a75a1ec20cbf52bef 100644
--- a/src/core/SkPictureRecord.cpp
+++ b/src/core/SkPictureRecord.cpp
@@ -293,15 +293,14 @@ static bool match(SkWriter32* writer, uint32_t offset,
     int numMatched;
     for (numMatched = 0; numMatched < numCommands && curOffset < writer->bytesWritten(); ++numMatched) {
         DrawType op = peek_op_and_size(writer, curOffset, &curSize);
-        while (NOOP == op && curOffset < writer->bytesWritten()) {
+        while (NOOP == op) {
             curOffset += curSize;
+            if (curOffset >= writer->bytesWritten()) {
+                return false;
+            }
             op = peek_op_and_size(writer, curOffset, &curSize);
         }
 
-        if (curOffset >= writer->bytesWritten()) {
-            return false; // ran out of byte stream
-        }
-
         if (kDRAW_BITMAP_FLAVOR == pattern[numMatched]) {
             if (DRAW_BITMAP != op && DRAW_BITMAP_MATRIX != op &&
                 DRAW_BITMAP_NINE != op && DRAW_BITMAP_RECT_TO_RECT != op) {
@@ -1649,6 +1648,11 @@ void SkPictureRecord::addPoints(const SkPoint pts[], int count) {
 #endif
 }
 
+void SkPictureRecord::addNoOp() {
+    size_t size = kUInt32Size; // op
+    this->addDraw(NOOP, &size);
+}
+
 void SkPictureRecord::addRect(const SkRect& rect) {
 #ifdef SK_DEBUG_SIZE
     size_t start = fWriter.bytesWritten();