Revert "SkBitmap now really stores SkImageInfo -- config is just a ruse"

tests/ImageDecodingTest.cpp

Index: tests/ImageDecodingTest.cpp
diff --git a/tests/ImageDecodingTest.cpp b/tests/ImageDecodingTest.cpp
index 2e0225a26195bdcaf1d39a9c143f6818ea53f349..81f900660d6d5b259fcf261ad8ffb4ca024efa6e 100644
--- a/tests/ImageDecodingTest.cpp
+++ b/tests/ImageDecodingTest.cpp
@@ -333,7 +333,10 @@ static SkPixelRef* install_pixel_ref(SkBitmap* bitmap,
     SkASSERT(stream != NULL);
     SkASSERT(stream->rewind());
     SkASSERT(stream->unique());
-    SkColorType colorType = bitmap->colorType();
+    SkColorType colorType;
+    if (!SkBitmapConfigToColorType(bitmap->config(), &colorType)) {
+        return NULL;
+    }
     SkDecodingImageGenerator::Options opts(sampleSize, ditherImage, colorType);
     SkAutoTDelete<SkImageGenerator> gen(
         SkDecodingImageGenerator::Create(stream, opts));