String16: remove integer overflows

Bug: 73826242
Test: manual
Change-Id: I32e13d61b944c1a527cf2d95473552d246e322be
Merged-In: I32e13d61b944c1a527cf2d95473552d246e322be
(cherry picked from commit d0648d8dc61fe9ac39d2cd150a332b385a334bdc)
1 file changed