If any did, they were very, very few.
The California Gold Rush started in 1849; Japan was isolationist until 1853, when the United States sent warships over to demand access to Japanese ports. No treaty was signed with the United States until several years after the Gold Rush was over.
So while I can't say for sure that not one single Japanese heard that there was gold in America and came over during that time...it wouldn't surprise me much if none came. If any did, they were an extreme minority.