Refactor how we store and use samplers in Ganesh

src/gpu/effects/GrYUVEffect.cpp

Index: src/gpu/effects/GrYUVEffect.cpp
diff --git a/src/gpu/effects/GrYUVEffect.cpp b/src/gpu/effects/GrYUVEffect.cpp
index 97ef663bb7bd18e5c187ccb77e9734fb66e97d10..20865f43b5e57437353032784236ab10917c34a8 100644
--- a/src/gpu/effects/GrYUVEffect.cpp
+++ b/src/gpu/effects/GrYUVEffect.cpp
@@ -100,19 +100,23 @@ public:
 
         void emitCode(EmitArgs& args) override {
             GrGLSLFPFragmentBuilder* fragBuilder = args.fFragBuilder;
+            GrGLSLUniformHandler* uniformHandler = args.fUniformHandler;
 
             const char* colorSpaceMatrix = nullptr;
-            fMatrixUni = args.fUniformHandler->addUniform(kFragment_GrShaderFlag,
-                                                          kMat44f_GrSLType, kDefault_GrSLPrecision,
-                                                          "ColorSpaceMatrix", &colorSpaceMatrix);
+            fMatrixUni = uniformHandler->addUniform(kFragment_GrShaderFlag,
+                                                    kMat44f_GrSLType, kDefault_GrSLPrecision,
+                                                    "ColorSpaceMatrix", &colorSpaceMatrix);
             fragBuilder->codeAppendf("%s = vec4(", args.fOutputColor);
-            fragBuilder->appendTextureLookup(args.fTexSamplers[0], args.fCoords[0].c_str(),
+            fragBuilder->appendTextureLookup(uniformHandler->getSampler(args.fTexSamplers[0]),
+                                             args.fCoords[0].c_str(),
                                              args.fCoords[0].getType());
             fragBuilder->codeAppend(".r,");
-            fragBuilder->appendTextureLookup(args.fTexSamplers[1], args.fCoords[1].c_str(),
+            fragBuilder->appendTextureLookup(uniformHandler->getSampler(args.fTexSamplers[1]),
+                                             args.fCoords[1].c_str(),
                                              args.fCoords[1].getType());
             fragBuilder->codeAppend(".r,");
-            fragBuilder->appendTextureLookup(args.fTexSamplers[2], args.fCoords[2].c_str(),
+            fragBuilder->appendTextureLookup(uniformHandler->getSampler(args.fTexSamplers[2]),
+                                             args.fCoords[2].c_str(),
                                              args.fCoords[2].getType());
             fragBuilder->codeAppendf(".r, 1.0) * %s;", colorSpaceMatrix);
         }