Don't serialize anything for SkEmptyShader.

gm/badpaint.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 #include "SkCanvas.h"
 #include "SkShader.h"
@@ skipping 12 matching lines @@
     void onOnceBeforeDraw() override {
         SkBitmap emptyBmp;
 
         SkBitmap blueBmp;
         blueBmp.allocN32Pixels(10, 10);
         blueBmp.eraseColor(SK_ColorBLUE);
 
         SkMatrix badMatrix;
         badMatrix.setAll(0, 0, 0, 0, 0, 0, 0, 0, 0);
 
-#if 0 // This crashes pipe!
         // Empty bitmap.
         fPaints.push_back().setColor(SK_ColorGREEN);
         fPaints.back().setShader(SkShader::CreateBitmapShader(emptyBmp, SkShader::kClamp_TileMode,
                                                               SkShader::kClamp_TileMode))->unref();
-#endif
 
         // Non-invertible local matrix.
         fPaints.push_back().setColor(SK_ColorGREEN);
         fPaints.back().setShader(SkShader::CreateBitmapShader(blueBmp, SkShader::kClamp_TileMode,
                                                               SkShader::kClamp_TileMode,
                                                               &badMatrix))->unref();
     }
 
     void onDraw(SkCanvas* canvas) override {
         SkRect rect = SkRect::MakeXYWH(10, 10, 80, 80);
         for (int i = 0; i < fPaints.count(); ++i) {
             canvas->drawRect(rect, fPaints[i]);
         }
     }
 
 private:
     SkTArray<SkPaint> fPaints;
 
     typedef skiagm::GM INHERITED;
 };
 
 /////////////////////////////////////////////////////////////////////////////////////
 
 DEF_GM( return SkNEW(BadPaintGM); )