Makes GrGLProgramDesc's key store the lengths as well as offsets of the effect keys.

src/gpu/gl/GrGLProgramEffects.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrGLProgramEffects_DEFINED
 #define GrGLProgramEffects_DEFINED
 
 #include "GrBackendEffectFactory.h"
+#include "GrGLUniformManager.h"
 #include "GrTexture.h"
 #include "GrTextureAccess.h"
-#include "GrGLUniformManager.h"
 
 class GrEffect;
 class GrEffectStage;
 class GrGLVertexProgramEffectsBuilder;
 class GrGLShaderBuilder;
 class GrGLFullShaderBuilder;
 class GrGLFragmentOnlyShaderBuilder;
 
 /**
  * This class encapsulates an array of GrGLEffects and their supporting data (coord transforms
  * and textures). It is built with GrGLProgramEffectsBuilder, then used to manage the necessary GL
  * state and shader uniforms.
  */
 class GrGLProgramEffects : public SkRefCnt {
 public:
     typedef GrBackendEffectFactory::EffectKey EffectKey;
     typedef GrGLUniformManager::UniformHandle UniformHandle;
 
     /**
-     * These methods generate different portions of an effect's final key.
+     * This class emits some of the code inserted into the shaders for an effect. The code it
+     * creates may be dependent on properties of the effect that the effect itself doesn't use
+     * in its key (e.g. the pixel format of textures used). So this class inserts a meta-key for
+     * every effect using this function. It is also responsible for inserting the effect's class ID
+     * which must be different for every GrEffect subclass. It can fail if an effect uses too many
+     * textures, attributes, etc for the space allotted in the meta-key.
      */
-    static EffectKey GenAttribKey(const GrDrawEffect&);
-    static EffectKey GenTransformKey(const GrDrawEffect&);
-    static EffectKey GenTextureKey(const GrDrawEffect&, const GrGLCaps&);
+    static bool GenEffectMetaKey(const GrDrawEffect&, const GrGLCaps&, GrEffectKeyBuilder*);
 
     virtual ~GrGLProgramEffects();
 
     /**
      * Assigns a texture unit to each sampler. It starts on *texUnitIdx and writes the next
      * available unit to *texUnitIdx when it returns.
      */
     void initSamplers(const GrGLUniformManager&, int* texUnitIdx);
 
     /**
@@ skipping 42 matching lines @@
 
     private:
         UniformHandle fSamplerUniform;
         uint32_t      fConfigComponentMask;
         char          fSwizzle[5];
     };
 
     typedef SkTArray<TextureSampler> TextureSamplerArray;
 
 protected:
+    /**
+     * Helpers for GenEffectMetaKey.
+     */
+    static EffectKey GenAttribKey(const GrDrawEffect&);
+    static EffectKey GenTransformKey(const GrDrawEffect&);
+    static EffectKey GenTextureKey(const GrDrawEffect&, const GrGLCaps&);
+
     GrGLProgramEffects(int reserveCount)
         : fGLEffects(reserveCount)
         , fSamplers(reserveCount) {
     }
 
     /**
      * Helper for emitEffect() in a subclasses. Emits uniforms for an effect's texture accesses and
      * appends the necessary data to the TextureSamplerArray* object so effects can add texture
      * lookups to their code. This method is only meant to be called during the construction phase.
      */
@@ skipping 206 matching lines @@
     GrGLProgramEffects* finish() { return fProgramEffects.detach(); }
 
 private:
     GrGLFragmentOnlyShaderBuilder*          fBuilder;
     SkAutoTDelete<GrGLPathTexGenProgramEffects> fProgramEffects;
 
     typedef GrGLProgramEffectsBuilder INHERITED;
 };
 
 #endif