fix the build error of SkiaExample -- use setColorType, not setConfig

experimental/SkiaExamples/SkExample.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  */
 
 #include "SkExample.h"
@@ skipping 50 matching lines @@
         SkSafeUnref(fRenderTarget);
         fRenderTarget = NULL;
 
         detach();
     }
 }
 
 bool SkExampleWindow::setupBackend(DeviceType type) {
     fType = type;
 
-    this->setConfig(SkBitmap::kARGB_8888_Config);
+    this->setColorType(kRGBA_8888_SkColorType);
     this->setVisibleP(true);
     this->setClipToBounds(false);
 
     bool result = attach(kNativeGL_BackEndType, 0 /*msaa*/, &fAttachmentInfo);
     if (false == result) {
         SkDebugf("Not possible to create backend.\n");
         detach();
         return false;
     }
 
@@ skipping 103 matching lines @@
             SkDebugf("No SkExample that matches your query\n");
         }
     }
     return true;
 }
 
 SkOSWindow* create_sk_window(void* hwnd, int argc, char** argv) {
     SkCommandLineFlags::Parse(argc, argv);
     return new SkExampleWindow(hwnd);
 }