Adjusting code interface

glslang/include/intermediate.h -> Add a new interface to set TIntermBranch's expression.

glslang/include/Types.h -> Add interface to set Type's basicType and add interface to get basicType form a TSampler.

glslang/MachineIndependent/intermediate.cpp -> Part of the code in createConversion been encapsulating as a new function called buildConvertOp

glslang/MachineIndependent/localintermediate.h -> Export createConversion and
buildConvertOp as a public function

glslang/Public/ShaderLang.h -> Add interface to get shader object and shader source.

glslang/Include/Types.h

@@ -135,6 +135,8 @@ struct TSampler {   // misnomer now; includes images, textures without sampler,
     bool isYuv()         const { return yuv; }
 #endif
     void setCombined(bool c) { combined = c; }
+    void setBasicType(TBasicType t) { type = t; };
+    TBasicType getBasicType()  const { return type; };
     bool isShadow()      const { return shadow; }
     bool isArrayed()     const { return arrayed; }
 
@@ -2184,7 +2186,8 @@ public:
     const TTypeList* getStruct() const { assert(isStruct()); return structure; }
     void setStruct(TTypeList* s) { assert(isStruct()); structure = s; }
     TTypeList* getWritableStruct() const { assert(isStruct()); return structure; }  // This should only be used when known to not be sharing with other threads
-
+    void setBasicType(const TBasicType& t) { basicType = t; }
+    
     int computeNumComponents() const
     {
         int components = 0;

glslang/Include/intermediate.h

@@ -1185,6 +1185,7 @@ public:
     virtual void traverse(TIntermTraverser*);
     TOperator getFlowOp() const { return flowOp; }
     TIntermTyped* getExpression() const { return expression; }
+    void setExpression(TIntermTyped* pExpression) { expression = pExpression; }
 protected:
     TOperator flowOp;
     TIntermTyped* expression;