Create GLSLUniformHandler class for gpu backend

src/effects/SkDisplacementMapEffect.cpp

Index: src/effects/SkDisplacementMapEffect.cpp
diff --git a/src/effects/SkDisplacementMapEffect.cpp b/src/effects/SkDisplacementMapEffect.cpp
index fe918581c421b09ddc3fbe5a0465b60d3c25bce9..3370a76495c17d4dd28ecd48a584401c0ef9dfa7 100644
--- a/src/effects/SkDisplacementMapEffect.cpp
+++ b/src/effects/SkDisplacementMapEffect.cpp
@@ -19,8 +19,8 @@
 #include "effects/GrTextureDomain.h"
 #include "glsl/GrGLSLFragmentProcessor.h"
 #include "glsl/GrGLSLFragmentShaderBuilder.h"
-#include "glsl/GrGLSLProgramBuilder.h"
 #include "glsl/GrGLSLProgramDataManager.h"
+#include "glsl/GrGLSLUniformHandler.h"
 #endif
 
 namespace {
@@ -549,9 +549,9 @@ GrGLDisplacementMapEffect::~GrGLDisplacementMapEffect() {
 void GrGLDisplacementMapEffect::emitCode(EmitArgs& args) {
     const GrTextureDomain& domain = args.fFp.cast<GrDisplacementMapEffect>().domain();
 
-    fScaleUni = args.fBuilder->addUniform(GrGLSLProgramBuilder::kFragment_Visibility,
-                                          kVec2f_GrSLType, kDefault_GrSLPrecision, "Scale");
-    const char* scaleUni = args.fBuilder->getUniformCStr(fScaleUni);
+    fScaleUni = args.fUniformHandler->addUniform(GrGLSLUniformHandler::kFragment_Visibility,
+                                                 kVec2f_GrSLType, kDefault_GrSLPrecision, "Scale");
+    const char* scaleUni = args.fUniformHandler->getUniformCStr(fScaleUni);
     const char* dColor = "dColor";
     const char* cCoords = "cCoords";
     const char* nearZero = "1e-6"; // Since 6.10352e−5 is the smallest half float, use
@@ -610,6 +610,7 @@ void GrGLDisplacementMapEffect::emitCode(EmitArgs& args) {
     fragBuilder->codeAppend("-vec2(0.5));\t\t");
 
     fGLDomain.sampleTexture(fragBuilder,
+                            args.fUniformHandler,
                             args.fGLSLCaps,
                             domain,
                             args.fOutputColor,