Step towards variable length effect keys.

src/effects/SkAlphaThresholdFilter.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 "SkAlphaThresholdFilter.h"
 #include "SkBitmap.h"
 #include "SkReadBuffer.h"
@@ skipping 30 matching lines @@
                                               SkScalar outerThreshold,
                                               SkImageFilter* input) {
     return SkNEW_ARGS(SkAlphaThresholdFilterImpl, (region, innerThreshold, outerThreshold, input));
 }
 
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
 #include "GrCoordTransform.h"
 #include "GrEffect.h"
 #include "gl/GrGLEffect.h"
+#include "gl/GrGLShaderBuilder.h"
 #include "GrTBackendEffectFactory.h"
 #include "GrTextureAccess.h"
 
 #include "SkGr.h"
 
 class GrGLAlphaThresholdEffect;
 
 class AlphaThresholdEffect : public GrEffect {
 
 public:
@@ skipping 298 matching lines @@
                                                   (U8CPU)(SkColorGetG(source) * scale),
                                                   (U8CPU)(SkColorGetB(source) * scale));
                 }
             }
             dptr[y * dst->width() + x] = output_color;
         }
     }
 
     return true;
 }