EXPECT_EQ("+8698812", formatter_->InputDigit('2', &result_));
EXPECT_EQ("+86988123", formatter_->InputDigit('3', &result_));
EXPECT_EQ("+869881234", formatter_->InputDigit('4', &result_));
EXPECT_EQ("+8698812", formatter_->InputDigit('2', &result_));
EXPECT_EQ("+86988123", formatter_->InputDigit('3', &result_));
EXPECT_EQ("+869881234", formatter_->InputDigit('4', &result_));