remove alphatype from colortable

bench/RepeatTileBench.cpp

Index: bench/RepeatTileBench.cpp
diff --git a/bench/RepeatTileBench.cpp b/bench/RepeatTileBench.cpp
index cf29b6a460ee19fdc03e56deb1100726bda5c142..cf147d8c21334b0652347c7451234e4f058547cb 100644
--- a/bench/RepeatTileBench.cpp
+++ b/bench/RepeatTileBench.cpp
@@ -63,7 +63,7 @@ static void convert_to_index666(const SkBitmap& src, SkBitmap* dst) {
             }
         }
     }
-    SkColorTable* ctable = new SkColorTable(storage, 216, kOpaque_SkAlphaType);
+    SkColorTable* ctable = new SkColorTable(storage, 216);
     dst->allocPixels(SkImageInfo::Make(src.width(), src.height(),
                                        kIndex_8_SkColorType, kOpaque_SkAlphaType),
                      NULL, ctable);