Add scanline decoding to SkCodec.

src/codec/SkCodec_libbmp.cpp

Index: src/codec/SkCodec_libbmp.cpp
diff --git a/src/codec/SkCodec_libbmp.cpp b/src/codec/SkCodec_libbmp.cpp
index e9551cbb6ff098338da2ec16383488b6332702a3..8c3ac91a62ba16d1fecebf9fb5ba96862a9a67c6 100644
--- a/src/codec/SkCodec_libbmp.cpp
+++ b/src/codec/SkCodec_libbmp.cpp
@@ -459,11 +459,11 @@ SkCodec::Result SkBmpCodec::onGetPixels(const SkImageInfo& dstInfo,
     if (!this->rewindIfNeeded()) {
         return kCouldNotRewind;
     }
-    if (dstInfo.dimensions() != this->getOriginalInfo().dimensions()) {
+    if (dstInfo.dimensions() != this->getInfo().dimensions()) {
         SkDebugf("Error: scaling not supported.\n");
         return kInvalidScale;
     }
-    if (!conversion_possible(dstInfo, this->getOriginalInfo())) {
+    if (!conversion_possible(dstInfo, this->getInfo())) {
         SkDebugf("Error: cannot convert input type to output type.\n");
         return kInvalidConversion;
     }