removed const from ASTVarDeclaration::fName to avoid a Chromium build failure

src/sksl/ast/SkSLASTVarDeclaration.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_ASTVARDECLARATIONS
 #define SKSL_ASTVARDECLARATIONS
 
@@ skipping 26 matching lines @@
             } else {
                 result += "[]";
             }
         }
         if (fValue) {
             result += " = " + fValue->description();
         }
         return result;        
     }
 
-    const std::string fName;
+    std::string fName;
 
     // array sizes, if any. e.g. 'foo[3][]' has sizes [3, null]
     std::vector<std::unique_ptr<ASTExpression>> fSizes;
 
     // initial value, may be null
     std::unique_ptr<ASTExpression> fValue;
 };
 
 /**
  * A variable declaration statement, which may consist of one or more individual variables.
@@ skipping 21 matching lines @@
     const ASTModifiers fModifiers;
     const std::unique_ptr<ASTType> fType;
     const std::vector<ASTVarDeclaration> fVars;
 
     typedef ASTDeclaration INHERITED;
 };
 
 } // namespace
 
 #endif