Change old PRG to be SkLCGRandom; change new one to SkRandom

src/effects/SkArithmeticMode.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 "SkArithmeticMode.h"
 #include "SkColorPriv.h"
 #include "SkFlattenableBuffers.h"
@@ skipping 397 matching lines @@
     EffectKey bgKey = 0;
     if (bgTex) {
         bgKey = GrGLEffectMatrix::GenKey(GrEffect::MakeDivByTextureWHMatrix(bgTex),
                                          drawEffect,
                                          GrGLArithmeticEffect::kCoordsType,
                                          bgTex);
     }
     return bgKey;
 }
 
-GrEffectRef* GrArithmeticEffect::TestCreate(SkMWCRandom* rand,
+GrEffectRef* GrArithmeticEffect::TestCreate(SkRandom* rand,
                                             GrContext*,
                                             const GrDrawTargetCaps&,
                                             GrTexture*[]) {
     float k1 = rand->nextF();
     float k2 = rand->nextF();
     float k3 = rand->nextF();
     float k4 = rand->nextF();
 
     static AutoEffectUnref gEffect(SkNEW_ARGS(GrArithmeticEffect, (k1, k2, k3, k4, NULL)));
     return CreateEffectRef(gEffect);
@@ skipping 14 matching lines @@
                                              background);
     }
     return true;
 }
 
 #endif
 
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkArithmeticMode)
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkArithmeticMode_scalar)
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END