use SkColorType instead of SkBitmap::Config in samplecode

BUG=skia:
R=reed@google.com

Author: reed@chromium.org

Review URL: https://codereview.chromium.org/169063002

git-svn-id: http://skia.googlecode.com/svn/trunk@13473 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/samplecode/SampleSlides.cpp b/samplecode/SampleSlides.cpp
index 4f68032..26cfc7d 100644
--- a/samplecode/SampleSlides.cpp
+++ b/samplecode/SampleSlides.cpp
@@ -686,8 +686,7 @@
         fIndex = 0;
 
         SkBitmap bm;
-        bm.setConfig(SkBitmap::kARGB_8888_Config, 1024, 768);
-        bm.allocPixels();
+        bm.allocN32Pixels(1024, 768);
         SkCanvas canvas(bm);
         SkScalar s = SkIntToScalar(1024) / 640;
         canvas.scale(s, s);