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

src/gpu/effects/GrBicubicEffect.cpp

 #include "GrBicubicEffect.h"
 
 #define DS(x) SkDoubleToScalar(x)
 
 const SkScalar GrBicubicEffect::gMitchellCoefficients[16] = {
     DS( 1.0 / 18.0), DS(-9.0 / 18.0), DS( 15.0 / 18.0), DS( -7.0 / 18.0),
     DS(16.0 / 18.0), DS( 0.0 / 18.0), DS(-36.0 / 18.0), DS( 21.0 / 18.0),
     DS( 1.0 / 18.0), DS( 9.0 / 18.0), DS( 27.0 / 18.0), DS(-21.0 / 18.0),
     DS( 0.0 / 18.0), DS( 0.0 / 18.0), DS( -6.0 / 18.0), DS(  7.0 / 18.0),
 };
@@ skipping 143 matching lines @@
 }
 
 void GrBicubicEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
     // FIXME:  Perhaps we can do better.
     *validFlags = 0;
     return;
 }
 
 GR_DEFINE_EFFECT_TEST(GrBicubicEffect);
 
-GrEffectRef* GrBicubicEffect::TestCreate(SkMWCRandom* random,
+GrEffectRef* GrBicubicEffect::TestCreate(SkRandom* random,
                                          GrContext* context,
                                          const GrDrawTargetCaps&,
                                          GrTexture* textures[]) {
     int texIdx = random->nextBool() ? GrEffectUnitTest::kSkiaPMTextureIdx :
                                       GrEffectUnitTest::kAlphaTextureIdx;
     SkScalar coefficients[16];
     for (int i = 0; i < 16; i++) {
         coefficients[i] = random->nextSScalar1();
     }
     return GrBicubicEffect::Create(textures[texIdx], coefficients);
 }