start to remove lockPixels from bitmapshader

src/core/SkPixelRef.cpp

Index: src/core/SkPixelRef.cpp
diff --git a/src/core/SkPixelRef.cpp b/src/core/SkPixelRef.cpp
index bc548a22a884923c88ec9b181c3ebbc067998abe..08775f24de96f86a653da58f89bcf29e6561583f 100644
--- a/src/core/SkPixelRef.cpp
+++ b/src/core/SkPixelRef.cpp
@@ -167,6 +167,14 @@ bool SkPixelRef::onLockPixelsAreWritable() const {
     return true;
 }
 
+bool SkPixelRef::onImplementsDecodeInto() {
+    return false;
+}
+
+bool SkPixelRef::onDecodeInto(int pow2, SkBitmap* bitmap) {
+    return false;
+}
+
 uint32_t SkPixelRef::getGenerationID() const {
     if (0 == fGenerationID) {
         fGenerationID = SkNextPixelRefGenerationID();