Use updated signature for decode in empty decoder.

src/ports/SkImageDecoder_empty.cpp

Index: src/ports/SkImageDecoder_empty.cpp
diff --git a/src/ports/SkImageDecoder_empty.cpp b/src/ports/SkImageDecoder_empty.cpp
index 410eef11b8924957e17c179fa2da69c9a865233c..43beb94e27fd112452db04ad94fe20e7d73e3207 100644
--- a/src/ports/SkImageDecoder_empty.cpp
+++ b/src/ports/SkImageDecoder_empty.cpp
@@ -23,7 +23,7 @@ bool SkImageDecoder::DecodeFile(const char file[], SkBitmap*, SkBitmap::Config,
     return false;
 }
 
-bool SkImageDecoder::decode(SkStream*, SkBitmap* bitmap, SkBitmap::Config pref, Mode) {
+bool SkImageDecoder::decode(SkStream*, SkBitmap*, SkBitmap::Config, Mode, bool) {
     return false;
 }