fix bug where hlsl2glsl was leaving duplicates in the uniforms list.

In buildUniformsAndLibFunctions(), std::unique only removes contiguous duplicates, so vector must first be sorted to remove them all.

hlslang/GLSLCodeGen/hlslLinker.cpp

@@ -729,6 +729,9 @@ void HlslLinker::buildUniformsAndLibFunctions(const FunctionSet& calledFunctions
 		libFunctions.insert( referencedFunctions.begin(), referencedFunctions.end());
 	}
 
+    // std::unique only removes contiguous duplicates, so vector must be sorted to remove them all
+    std::sort(constants.begin(), constants.end());
+
 	// Remove duplicates
 	constants.resize(std::unique(constants.begin(), constants.end()) - constants.begin());
 }