added constant folding & branch elimination to skslc

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 865876611ab87584b7617776fd5820165b1e6df8..2c7e5e476db017f8cb2324e727b451691d711f38 100644
--- a/src/gpu/glsl/GrGLSLShaderBuilder.cpp
+++ b/src/gpu/glsl/GrGLSLShaderBuilder.cpp
@@ -72,18 +72,7 @@ void GrGLSLShaderBuilder::appendTextureLookup(SkString* out,
                                               const char* coordName,
                                               GrSLType varyingType) const {
     const GrShaderVar& sampler = fProgramBuilder->samplerVariable(samplerHandle);
-    GrSLType samplerType = sampler.getType();
-    if (samplerType == kTexture2DRectSampler_GrSLType) {
-        if (varyingType == kVec2f_GrSLType) {
-            out->appendf("texture(%s, textureSize(%s) * %s)",
-                         sampler.c_str(), sampler.c_str(), coordName);
-        } else {
-            out->appendf("texture(%s, vec3(textureSize(%s) * %s.xy, %s.z))",
-                         sampler.c_str(), sampler.c_str(), coordName, coordName);
-        }
-    } else {
-        out->appendf("texture(%s, %s)", sampler.c_str(), coordName);
-    }
+    out->appendf("texture(%s, %s)", sampler.c_str(), coordName);
     append_texture_swizzle(out, fProgramBuilder->samplerSwizzle(samplerHandle));
 }