use colortype instead of config

clone of https://codereview.chromium.org/305133006/

TBR=

BUG=skia:

Author: reed@google.com

Review URL: https://codereview.chromium.org/301233011
diff --git a/src/utils/SkBitmapHasher.cpp b/src/utils/SkBitmapHasher.cpp
index bd038dd..32ff1cb 100644
--- a/src/utils/SkBitmapHasher.cpp
+++ b/src/utils/SkBitmapHasher.cpp
@@ -55,7 +55,7 @@
     }
 
     // Hmm, that didn't work. Maybe if we create a new
-    // kARGB_8888_Config version of the bitmap it will work better?
+    // version of the bitmap it will work better?
     SkBitmap copyBitmap;
     if (!bitmap.copyTo(&copyBitmap, kN32_SkColorType)) {
         return false;