RPM only knows about software installed by RPM and registered in the RPMDB. Installing other versions of software in arbitrary locations doesn't mean RPM knows about it.
Your options are to install a newer GCC via RPM or install chrome using the --nodeps
option, which tells RPM not to check dependencies. If you choose the second approach then it's your responsibility to make sure the libraries will be found at runtime, e.g. by setting LD_LIBRARY_PATH
or some other method such as adding the directory to the ldconfig
cache.