Refactor how we store and use samplers in Ganesh

src/gpu/glsl/GrGLSLShaderBuilder.cpp

Index: src/gpu/glsl/GrGLSLShaderBuilder.cpp
diff --git a/src/gpu/glsl/GrGLSLShaderBuilder.cpp b/src/gpu/glsl/GrGLSLShaderBuilder.cpp
index 1031f84460acf3089afac81ee8ffd5c4f93c5005..b866fbce2a3b941c7272c1dd3941d7121aaf9558 100644
--- a/src/gpu/glsl/GrGLSLShaderBuilder.cpp
+++ b/src/gpu/glsl/GrGLSLShaderBuilder.cpp
@@ -68,28 +68,28 @@ void GrGLSLShaderBuilder::appendTextureLookup(SkString* out,
                                               GrSLType varyingType) const {
     const GrGLSLCaps* glslCaps = fProgramBuilder->glslCaps();
     GrGLSLUniformHandler* uniformHandler = fProgramBuilder->uniformHandler();
-    GrSLType samplerType = uniformHandler->getUniformVariable(sampler.fSamplerUniform).getType();
+    GrSLType samplerType = sampler.type();
     if (samplerType == kSampler2DRect_GrSLType) {
         if (varyingType == kVec2f_GrSLType) {
             out->appendf("%s(%s, textureSize(%s) * %s)",
                          GrGLSLTexture2DFunctionName(varyingType, samplerType,
                                                      glslCaps->generation()),
-                         uniformHandler->getUniformCStr(sampler.fSamplerUniform),
-                         uniformHandler->getUniformCStr(sampler.fSamplerUniform),
+                         sampler.getSamplerFunctionName(),
+                         sampler.getSamplerFunctionName(),
                          coordName);
         } else {
             out->appendf("%s(%s, vec3(textureSize(%s) * %s.xy, %s.z))",
                          GrGLSLTexture2DFunctionName(varyingType, samplerType,
                                                      glslCaps->generation()),
-                         uniformHandler->getUniformCStr(sampler.fSamplerUniform),
-                         uniformHandler->getUniformCStr(sampler.fSamplerUniform),
+                         sampler.getSamplerFunctionName(),
+                         sampler.getSamplerFunctionName(),
                          coordName,
                          coordName);
         }
     } else {
         out->appendf("%s(%s, %s)",
                      GrGLSLTexture2DFunctionName(varyingType, samplerType, glslCaps->generation()),
-                     uniformHandler->getUniformCStr(sampler.fSamplerUniform),
+                     sampler.getSamplerFunctionName(),
                      coordName);
     }