rewrite_to_chrome_style: Make const decisions aware of const variables

tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp

Index: tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
diff --git a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
index 5141ccf6bda64f71f78f291fa5f2cba57a88a038..4014d97e902b92bfb5b410f313831660b31aa915 100644
--- a/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
+++ b/tools/clang/rewrite_to_chrome_style/RewriteToChromeStyle.cpp
@@ -409,8 +409,11 @@ bool CanBeEvaluatedAtCompileTime(const clang::Stmt* stmt,
     case clang::Stmt::DeclRefExprClass: {
       auto* declref = clang::dyn_cast<clang::DeclRefExpr>(expr);
       auto* decl = declref->getDecl();
-      if (clang::dyn_cast<clang::VarDecl>(decl))
+      if (auto* vardecl = clang::dyn_cast<clang::VarDecl>(decl)) {
+        if (auto* initializer = vardecl->getInit())
+          return CanBeEvaluatedAtCompileTime(initializer, context);
         return false;
+      }
       break;
     }