Merge commit 'd7ce227bcb854f048124bbc487eba844c6599142' * commit 'd7ce227bcb854f048124bbc487eba844c6599142': Fix String8::operator+
Merge commit 'd7ce227bcb854f048124bbc487eba844c6599142' * commit 'd7ce227bcb854f048124bbc487eba844c6599142': Fix String8::operator+