Refactor GrGLUniformManager::UniformHandle to initialize itself by default

src/effects/SkMatrixConvolutionImageFilter.cpp

 /*
  * Copyright 2012 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkMatrixConvolutionImageFilter.h"
 #include "SkBitmap.h"
 #include "SkColorPriv.h"
@@ skipping 333 matching lines @@
     UniformHandle       fBiasUni;
 
     GrGLEffectMatrix    fEffectMatrix;
 
     typedef GrGLEffect INHERITED;
 };
 
 GrGLMatrixConvolutionEffect::GrGLMatrixConvolutionEffect(const GrBackendEffectFactory& factory,
                                                          const GrDrawEffect& drawEffect)
     : INHERITED(factory)
-    , fKernelUni(GrGLUniformManager::kInvalidUniformHandle)
-    , fImageIncrementUni(GrGLUniformManager::kInvalidUniformHandle)
-    , fTargetUni(GrGLUniformManager::kInvalidUniformHandle)
-    , fGainUni(GrGLUniformManager::kInvalidUniformHandle)
-    , fBiasUni(GrGLUniformManager::kInvalidUniformHandle)
     , fEffectMatrix(drawEffect.castEffect<GrMatrixConvolutionEffect>().coordsType()) {
     const GrMatrixConvolutionEffect& m = drawEffect.castEffect<GrMatrixConvolutionEffect>();
     fKernelSize = m.kernelSize();
     fTileMode = m.tileMode();
     fConvolveAlpha = m.convolveAlpha();
 }
 
 static void appendTextureLookup(GrGLShaderBuilder* builder,
                                 const GrGLShaderBuilder::TextureSampler& sampler,
                                 const char* coord,
@@ skipping 209 matching lines @@
                                                 fBias,
                                                 fTarget,
                                                 fTileMode,
                                                 fConvolveAlpha);
     return true;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #endif