Merge SkCodec with SkScanlineDecoder

dm/DM.cpp

Index: dm/DM.cpp
diff --git a/dm/DM.cpp b/dm/DM.cpp
index 11581fda81fc71e7d30a2aa9a226fe2b45b3385a..0faca8f7c3e1f1250cbf4971910cf0d37faa890f 100644
--- a/dm/DM.cpp
+++ b/dm/DM.cpp
@@ -311,6 +311,12 @@ static void push_codec_srcs(Path path) {
         }
     }
 
+    if (path.endsWith(".ico") || path.endsWith(".ICO")) {
+        // FIXME: skbug.com/4404: ICO does not have the ability to decode scanlines, so we cannot
+        // use SkScaledCodec with it.
+        return;
+    }
+
     // SkScaledCodec Scales
     // The native scales are included to make sure that SkScaledCodec defaults to the native
     // scaling strategy when possible.