Fill incomplete images in SkCodec parent class

src/codec/SkBmpCodec.cpp

Index: src/codec/SkBmpCodec.cpp
diff --git a/src/codec/SkBmpCodec.cpp b/src/codec/SkBmpCodec.cpp
index 406a603dceefe3916714cb9cf394baefac094d00..2de63b8a1db7507638b06978d3dadf123bf1db99 100644
--- a/src/codec/SkBmpCodec.cpp
+++ b/src/codec/SkBmpCodec.cpp
@@ -556,9 +556,9 @@ int32_t SkBmpCodec::getDstRow(int32_t y, int32_t height) {
  * we start filling from where we left off, but for kBottomUp we start
  * filling at the top of the image.
  */
-void* SkBmpCodec::getDstStartRow(void* dst, size_t dstRowBytes, int32_t y) const {
+void* SkBmpCodec::onGetFillDst(void* dst, size_t dstRowBytes, uint32_t decodedScanlines) const {
     return (SkScanlineDecoder::kTopDown_SkScanlineOrder == fRowOrder) ?
-            SkTAddOffset<void*>(dst, y * dstRowBytes) : dst;
+            INHERITED::onGetFillDst(dst, dstRowBytes, decodedScanlines) : dst;
 }
 
 /*
@@ -580,7 +580,7 @@ uint32_t SkBmpCodec::computeNumColors(uint32_t numColors) {
 class SkBmpScanlineDecoder : public SkScanlineDecoder {
 public:
     SkBmpScanlineDecoder(SkBmpCodec* codec)
-        : INHERITED(codec->getInfo())
+        : INHERITED(codec, codec->getInfo())
         , fCodec(codec)
     {}
 
@@ -610,7 +610,7 @@ public:
         return fCodec->prepareToDecode(dstInfo, options, inputColorPtr, inputColorCount);
     }
 
-    SkCodec::Result onGetScanlines(void* dst, int count, size_t rowBytes) override {
+    uint32_t onGetScanlines(void* dst, int count, size_t rowBytes) override {
         // Create a new image info representing the portion of the image to decode
         SkImageInfo rowInfo = this->dstInfo().makeWH(this->dstInfo().width(), count);
 
@@ -622,14 +622,10 @@ public:
         return fCodec->fRowOrder;
     }
 
-    int onGetY() const override {
-        return fCodec->getDstRow(this->INHERITED::onGetY(), this->dstInfo().height());
-    }
-
     // TODO(msarett): Override default skipping with something more clever.
 
 private:
-    SkAutoTDelete<SkBmpCodec> fCodec;
+    SkBmpCodec* fCodec; // Owned by parent class
 
     typedef SkScanlineDecoder INHERITED;
 };