    database/sql: Alter *DB.begin to return driver.ErrBadConn when driver.Conn.Begin returns driver.ErrBadConn Fixes issue 4433
    database/sql: Alter *DB.begin to return driver.ErrBadConn when driver.Conn.Begin returns driver.ErrBadConn
Fixes issue 4433

R=golang-dev, bradfitz
CC=golang-dev
https://codereview.appspot.com/6845094

Committer: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

scirelli/scirelli-go,bryanxu/go-zh,bryanxu/go-zh,sanjosh/sanjos100-tipc,scirelli/scirelli-go,rdp/rogerpack2005-golang,bryanxu/go-zh,bryanxu/go-zh,sanjosh/sanjos100-tipc,sanjosh/sanjos100-tipc,glycerine/jeaten-go-arrayof-structof,scirelli/scirelli-go,rdp/rogerpack2005-golang,scirelli/scirelli-go,rdp/rogerpack2005-golang,glycerine/jeaten-go-arrayof-structof,bryanxu/go-zh,sanjosh/sanjos100-tipc,rdp/rogerpack2005-golang,glycerine/jeaten-go-arrayof-structof,glycerine/jeaten-go-arrayof-structof,webfd/go-zh,mhennings/marcohennings-go,rdp/rogerpack2005-golang,webfd/go-zh,scirelli/scirelli-go,webfd/go-zh,d0f/go-zh,webfd/go-zh,glycerine/jeaten-go-arrayof-structof,d0f/go-zh,d0f/go-zh,bryanxu/go-zh,mhennings/marcohennings-go,mhennings/marcohennings-go,webfd/go-zh,d0f/go-zh,sanjosh/sanjos100-tipc,d0f/go-zh,d0f/go-zh,glycerine/jeaten-go-arrayof-structof,webfd/go-zh,mhennings/marcohennings-go,rdp/rogerpack2005-golang,scirelli/scirelli-go,bryanxu/go-zh,scirelli/scirelli-go,webfd/go-zh,mhennings/marcohennings-go,bryanxu/go-zh,mhennings/marcohennings-go,glycerine/jeaten-go-arrayof-structof,sanjosh/sanjos100-tipc,mhennings/marcohennings-go,scirelli/scirelli-go,rdp/rogerpack2005-golang,glycerine/jeaten-go-arrayof-structof,webfd/go-zh,rdp/rogerpack2005-golang,d0f/go-zh,sanjosh/sanjos100-tipc,mhennings/marcohennings-go,sanjosh/sanjos100-tipc,d0f/go-zh