Remove uses of SkImageDecoder from gms

gm/copyTo4444.cpp

Index: gm/copyTo4444.cpp
diff --git a/gm/copyTo4444.cpp b/gm/copyTo4444.cpp
index 635cc7b8344a6d789a0e5d85985cec72dd2e130d..64f2c607467b276f6a99daf859a754889caea892 100644
--- a/gm/copyTo4444.cpp
+++ b/gm/copyTo4444.cpp
@@ -9,7 +9,6 @@
 
 #include "Resources.h"
 #include "SkCanvas.h"
-#include "SkImageDecoder.h"
 #include "SkOSFile.h"
 
 namespace skiagm {
@@ -32,9 +31,7 @@ protected:
 
     virtual void onDraw(SkCanvas* canvas) {
         SkBitmap bm, bm4444;
-        SkString pngFilename = GetResourcePath("mandrill_512.png");
-        if (!SkImageDecoder::DecodeFile(pngFilename.c_str(), &bm, kN32_SkColorType,
-                                        SkImageDecoder::kDecodePixels_Mode)) {
+        if (!GetResourceAsBitmap("mandrill_512.png", &bm)) {
             SkDebugf("Could not decode the file. Did you forget to set the "
                      "resourcePath?\n");
             return;