Defining new color constat for transparent color
Review URL: https://codereview.appspot.com/6901044

git-svn-id: http://skia.googlecode.com/svn/trunk@6696 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gm/tilemodes.cpp b/gm/tilemodes.cpp
index ab4ea0a..d51fce2 100644
--- a/gm/tilemodes.cpp
+++ b/gm/tilemodes.cpp
@@ -22,7 +22,7 @@
 static void makebm(SkBitmap* bm, SkBitmap::Config config, int w, int h) {
     bm->setConfig(config, w, h);
     bm->allocPixels();
-    bm->eraseColor(0);
+    bm->eraseColor(SK_ColorTRANSPARENT);
 
     SkCanvas    canvas(*bm);
     SkPoint     pts[] = { { 0, 0 }, { SkIntToScalar(w), SkIntToScalar(h)} };