Fix conversion from int to float64

[suzuki-shunsuke]

Cherry pick commits from google#753 .

$ git cherry-pick ac39251cade36bde3062ddf2a007a7d91828eab9 cf5c57e462b6d3aa2d04c89cde6de02571d3941a
[fix-convert-int-to-float64-2 165afaa] fix: fix conversion from int to float64
 Date: Mon Jun 3 12:44:05 2024 +0900
 1 file changed, 1 insertion(+), 1 deletion(-)
[fix-convert-int-to-float64-2 e121701] fix: fix a compile error
 Date: Mon Jun 3 12:53:42 2024 +0900
 1 file changed, 9 insertions(+), 1 deletion(-)