[AST][NFC] Pack CXXOperatorCallExpr

Use the space available in the bit-fields of Stmt.
This saves 8 bytes per CXXOperatorCallExpr. NFC.

llvm-svn: 349924
diff --git a/clang/lib/Serialization/ASTWriterStmt.cpp b/clang/lib/Serialization/ASTWriterStmt.cpp
index 3a14c39..c7527aa 100644
--- a/clang/lib/Serialization/ASTWriterStmt.cpp
+++ b/clang/lib/Serialization/ASTWriterStmt.cpp
@@ -1303,8 +1303,8 @@
 void ASTStmtWriter::VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
   VisitCallExpr(E);
   Record.push_back(E->getOperator());
-  Record.AddSourceRange(E->Range);
   Record.push_back(E->getFPFeatures().getInt());
+  Record.AddSourceRange(E->Range);
   Code = serialization::EXPR_CXX_OPERATOR_CALL;
 }