Use memoization to avoid repeated recomputation of nested
node sizes. Speeds up testdata/slow.input by several orders
of magnitude.

- added respective test case
- added timeout to test code
- deleted some unrelated unused code

Fixes #1628.

R=rsc, r
CC=golang-dev
https://golang.org/cl/4274075

Trying to track down why this fails on some
people's machines.

R=rsc, adg, dsymonds
CC=golang-dev
https://golang.org/cl/4304041

Fixes #1625.

R=bradfitzgo, bradfitzwork, r2
CC=golang-dev
https://golang.org/cl/4295060

Also delete references to nacl.

R=rsc, r2
CC=golang-dev
https://golang.org/cl/4275060

R=golang-dev, bradfitzwork, rsc1, peterGo
CC=golang-dev
https://golang.org/cl/4271056

This change had already been made in revision 7371, but
was then undone with changes in revision 7606.

R=golang-dev, rsc1
CC=golang-dev
https://golang.org/cl/4239064

Fixes #1629.

R=rsc
CC=golang-dev
https://golang.org/cl/4291057

These timeouts are breaking tests in very slow
systems every once in a while.  I've noticed
problems when compiling the Ubuntu packages for
arm, specifically.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/4291058

Fixes #1622.

R=rsc, bradfitzgo
CC=golang-dev
https://golang.org/cl/4287063

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4279065

R=r, r2
CC=golang-dev
https://golang.org/cl/4275057

R=iant, dsymonds
CC=golang-dev
https://golang.org/cl/4300041

R=rsc
CC=golang-dev
https://golang.org/cl/4293056

R=rsc
CC=golang-dev
https://golang.org/cl/4284057

Also in the common case avoid unnecessary buffering in
the channel.
Removes 13 allocations per round trip. Now at 86, down from
144 a week ago.

R=rsc, bradfitzgo, r2, rsc1
CC=golang-dev
https://golang.org/cl/4277060

Reduces rpc test "mallocs per rpc round trip" by 4.

Gains ~8% on a localhost client/server RPC test.

R=rsc
CC=golang-dev
https://golang.org/cl/4284056

R=golang-dev, brainman, gri
CC=golang-dev
https://golang.org/cl/4277062

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/4299044

fixes #1617

R=rsc
CC=golang-dev
https://golang.org/cl/4277059

R=golang-dev, rsc1
CC=adg, golang-dev
https://golang.org/cl/4274069

The scanner returns slices into the original source
for token values. If those slices are making it into
the AST and from there into other long-living data
structures (e.g. godoc search), references to the
original source are kept around involuntarily.

For the current godoc and source tree, this change reduces
memory consumption after indexing and before GC by ~92MB
or almost 30%, and by ~10MB after GC (or about 6%).

R=rsc
CC=golang-dev
https://golang.org/cl/4273072

Fixes #1615.

R=dsymonds
CC=golang-dev
https://golang.org/cl/4277058

In conjunction with the non-blocking system call CL, this
gives about an 8% performance improvement on a client/server
test running on my local machine.

R=rsc, iant2
CC=golang-dev
https://golang.org/cl/4272057

Fixes #1614.

R=gri
CC=golang-dev
https://golang.org/cl/4290054

R=rsc
CC=golang-dev
https://golang.org/cl/3559041

- just an oversight; we were reallocating a buffer.
- use unsafe to avoid allocating storage for a string twice.

R=rsc
CC=golang-dev
https://golang.org/cl/4290056

R=dsymonds
CC=golang-dev
https://golang.org/cl/4291052

R=golang-dev, niemeyer, rsc1, rog, rsc
CC=golang-dev
https://golang.org/cl/4285047

R=r
CC=golang-dev
https://golang.org/cl/4248066

R=rsc, niemeyer, r2, rog, iant2, r
CC=golang-dev
https://golang.org/cl/4235060

R=r
CC=golang-dev
https://golang.org/cl/4272058

Permit system calls to be designated as non-blocking, meaning
that we simply call them without involving the scheduler.

This change by itself is mostly performance neutral.  In
combination with a following change to the net package there
is a performance advantage.

R=rsc, dfc, r2, iant2, rsc1
CC=golang-dev
https://golang.org/cl/4278055

R=ken2
CC=golang-dev
https://golang.org/cl/4278056

- use enc.err and dec.err instead of return values in deferred error catcher
- replace io.WriteString with buffer.WriteString

now at:
mallocs per encode of type Bench: 7
mallocs per decode of type Bench: 8

R=rsc
CC=golang-dev
https://golang.org/cl/4277057

R=brainman, rsc, rsc1
CC=golang-dev
https://golang.org/cl/4249064

R=rsc
CC=golang-dev
https://golang.org/cl/4271048

gobuilder: recognize CLs of the form weekly.DATE

R=rsc, r
CC=golang-dev
https://golang.org/cl/4282052

This just returns a ClientConn suitable for writing
proxy requests.  To be used in Transport.

R=rsc, petar-m
CC=golang-dev
https://golang.org/cl/4290052

(per rsc's suggestion)

R=rsc
CC=golang-dev
https://golang.org/cl/4276057

R=gri
CC=golang-dev
https://golang.org/cl/4280048