Revert of SkSL performance improvements

src/sksl/ir/SkSLForStatement.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
  
 #ifndef SKSL_FORSTATEMENT
 #define SKSL_FORSTATEMENT
 
 #include "SkSLExpression.h"
 #include "SkSLStatement.h"
-#include "SkSLSymbolTable.h"
 
 namespace SkSL {
 
 /**
  * A 'for' statement.
  */
 struct ForStatement : public Statement {
     ForStatement(Position position, std::unique_ptr<Statement> initializer, 
                  std::unique_ptr<Expression> test, std::unique_ptr<Expression> next, 
-                 std::unique_ptr<Statement> statement, std::shared_ptr<SymbolTable> symbols)
+                 std::unique_ptr<Statement> statement)
     : INHERITED(position, kFor_Kind)
     , fInitializer(std::move(initializer))
     , fTest(std::move(test))
     , fNext(std::move(next))
-    , fStatement(std::move(statement))
-    , fSymbols(symbols) {}
+    , fStatement(std::move(statement)) {}
 
     std::string description() const override {
         std::string result = "for (";
         if (fInitializer) {
             result += fInitializer->description();
         } 
         result += " ";
         if (fTest) {
             result += fTest->description();
         } 
         result += "; ";
         if (fNext) {
             result += fNext->description();
         }
         result += ") " + fStatement->description();
         return result;
     }
 
     const std::unique_ptr<Statement> fInitializer;
     const std::unique_ptr<Expression> fTest;
     const std::unique_ptr<Expression> fNext;
     const std::unique_ptr<Statement> fStatement;
-    const std::shared_ptr<SymbolTable> fSymbols;
 
     typedef Statement INHERITED;
 };
 
 } // namespace
 
 #endif