doc/go1.7.html: no concurrent calls of math/rand methods
doc/go1.7.html: no concurrent calls of math/rand methods

A follow-on to https://golang.org/cl/24852 that mentions the
documentation clarifications.

Updates #16308.

Change-Id: Ic2a6e1d4938d74352f93a6649021fb610efbfcd0
Reviewed-on: https://go-review.googlesource.com/24857
Run-TryBot: Ian Lance Taylor <87e9c6d529889242b7e184afb632328636553ab4@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Joe Tsai <7277d7402195d5c2006c89f45718cf82bb3e527f@gmail.com>
Reviewed-by: Josh Bleecher Snyder <cdc248cc4d32e4fbfe04e45228163bcecd48a0b9@gmail.com>

momchil-velikov/go,nawawi/go,vsekhar/elastic-go,nawawi/go,4ad/go,cloudflare/go,derekmarcotte/go,polyverse-security/go,golang/go,cloudflare/go,linux-on-ibm-z/go,ImJasonH/go,momchil-velikov/go,polyverse-security/go,momchil-velikov/go,golang/go,linux-on-ibm-z/go,linux-on-ibm-z/go,momchil-velikov/go,suncycheng/go,akutz/go,ImJasonH/go,codestation/go,momchil-velikov/go,linux-on-ibm-z/go,golang/go,vsekhar/elastic-go,polyverse-security/go,josharian/go,suncycheng/go,4ad/go,CAFxX/go,momchil-velikov/go,vsekhar/elastic-go,Cofyc/go,Cofyc/go,polyverse-security/go,derekmarcotte/go,polyverse-security/go,codestation/go,momchil-velikov/go,codestation/go,akutz/go,codestation/go,linux-on-ibm-z/go,Cofyc/go,suncycheng/go,suncycheng/go,akutz/go,suncycheng/go,CAFxX/go,goodlang/good,akutz/go,Cofyc/go,goodlang/good,christopher-henderson/Go,suncycheng/go,derekmarcotte/go,cloudflare/go,ImJasonH/go,vsekhar/elastic-go,4ad/go,codestation/go,golang/go,ImJasonH/go,4ad/go,nawawi/go,josharian/go,akutz/go,goodlang/good,nawawi/go,vsekhar/elastic-go,golang/go,cloudflare/go,josharian/go,CAFxX/go,goodlang/good,josharian/go,polyverse-security/go,goodlang/good,goodlang/good,nawawi/go,nawawi/go,Cofyc/go,nawawi/go,codestation/go,ImJasonH/go,derekmarcotte/go,cloudflare/go,derekmarcotte/go,polyverse-security/go,codestation/go,josharian/go,golang/go,josharian/go,suncycheng/go,akutz/go,cloudflare/go,4ad/go,akutz/go,golang/go,CAFxX/go,goodlang/good,akutz/go,4ad/go,golang/go,ImJasonH/go,CAFxX/go,vsekhar/elastic-go,linux-on-ibm-z/go,josharian/go,cloudflare/go,ImJasonH/go,polyverse-security/go,linux-on-ibm-z/go,linux-on-ibm-z/go,derekmarcotte/go,CAFxX/go,goodlang/good,suncycheng/go,josharian/go,Cofyc/go,derekmarcotte/go,vsekhar/elastic-go,Cofyc/go,cloudflare/go,Cofyc/go,CAFxX/go,vsekhar/elastic-go,derekmarcotte/go,nawawi/go,codestation/go,ImJasonH/go,4ad/go,momchil-velikov/go,CAFxX/go,4ad/go