Automated g4 rollback of changelist 19916.

Automated g4 rollback of changelist 19916.

*** Reason for rollback ***

broke build

*** Original change description ***

utf8: add InString routines for decoding in strings
reflect: add InterfaceValue.Get(), remove Empty
strconv: add Quote, CanBackquote
fmt:
	* %q go-quoted " string
	* %#q go-quoted ` string if possible, " string otherwise
	* %x hexadecimal string
	* anywhere a string is okay, *[]byte is okay
	* flags # 0 - + space
	* print value inside interface, not interface itself
	* tests

TBR=r
OCL=19920
CL=19920