Create GLSLUniformHandler class for gpu backend

src/gpu/gl/GrGLVaryingHandler.h

Index: src/gpu/gl/GrGLVaryingHandler.h
diff --git a/src/gpu/gl/GrGLVaryingHandler.h b/src/gpu/gl/GrGLVaryingHandler.h
index ab931debd7cb8e9c5ca8a6655adbbd5de57a593d..50a87adc033017dfa36bdbaeeeac5edf0469cd8f 100644
--- a/src/gpu/gl/GrGLVaryingHandler.h
+++ b/src/gpu/gl/GrGLVaryingHandler.h
@@ -21,7 +21,7 @@ public:
     // This function is used by the NVPR PathProcessor to add a varying directly into the fragment
     // shader since there is no vertex shader.
     VaryingHandle addPathProcessingVarying(const char* name, GrGLSLVertToFrag*,
-                                       GrSLPrecision fsPrecision = kDefault_GrSLPrecision);
+                                           GrSLPrecision fsPrecision = kDefault_GrSLPrecision);
 
 private:
     typedef GrGLProgramDataManager::VaryingInfo VaryingInfo;