instead of the origin.

This makes YCbCr match the other image types (e.g. RGBA, Gray) in
that an image's bounds is not restricted to the positive quadrant.

Also optimize the YCbCr draw code by hoisting some computation
outside of the loop.

benchmark              old ns/op    new ns/op    delta
draw.BenchmarkYCbCr      2544418      2373558   -6.72%

Like https://golang.org/cl/4681044/ I don't think a gofix is
feasible. People will have to make manual changes. On the other hand,
directly manipulating YCbCr images is relatively rare, compared to
RGBA images, and if other code just uses the jpeg and draw packages
instead of messing directly with a YCbCr's []byte representations,
then things should just continue to work.

R=r
CC=golang-dev
https://golang.org/cl/5558048

R=golang-dev, alex.brainman
CC=golang-dev
https://golang.org/cl/5532102

R=rsc, bradfitz
CC=golang-dev
https://golang.org/cl/5536068

Remove NewMD5, NewSHA1 and NewSHA256 in favor of using New and
explicitly importing the used hash-function. This way when using, for
example, HMAC with RIPEMD there's no md5, sha1 and sha256 linked in
through the hmac package.

A gofix rule is included, and applied to the standard library (3 files
altered).

This change is the result of a discussion at
https://golang.org/cl/5550043/ to pull the discussion about
deprecating these functions out of that issue.

R=golang-dev, agl
CC=golang-dev, r, rsc
https://golang.org/cl/5556058

Fixes #2660.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5557060

Fix originally from rogpeppe in 5414048 but was rolled
back due to test breakage.

This CL makes the test more robust to order of operations.

Fixes #2480 again.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5536072

R=golang-dev, bsiegert, r
CC=golang-dev
https://golang.org/cl/5549043

R=rsc
CC=golang-dev
https://golang.org/cl/5542052

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5532100

Thanks to 0xE2.0x9A.0x9B for the patch suggestion.

Fixes #2739.

R=r
CC=golang-dev
https://golang.org/cl/5536071

The previous version of all the node.String methods printed the parse
tree and was useful for developing the parse tree code. Now that that's done,
we might as well print the nodes using the standard template syntax.
It's much easier to read and makes error reporting look more natural.

Helps issue 2644.

R=rsc, n13m3y3r
CC=golang-dev
https://golang.org/cl/5553066

SysUnused is a direct call to madvise MADV_FREE.

R=sebastien.paolacci, rsc, minux.ma
CC=golang-dev
https://golang.org/cl/5531073

Redirect to the canonical path when the old path is accessed.

R=gri
CC=golang-dev
https://golang.org/cl/5536061

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5539063

        So as to give out stack trace for panic in examples.
        This behavior also matches the tests'.
        Fixes #2691.

R=golang-dev
CC=golang-dev
https://golang.org/cl/5554061

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5554064

Prep for Issue 2699

R=rsc
CC=golang-dev
https://golang.org/cl/5536045

Fixes #2737.

R=bradfitz
CC=golang-dev
https://golang.org/cl/5553062

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5554063

(Sending to r because of the API change.)

Over time we might want to add support for other key types.

While I was in the code, I also made the use of RawSubject the same
between Subject and Issuer when creating certificates.

R=r, rsc
CC=golang-dev
https://golang.org/cl/5554049

(Sending to r because of the API change.)

This change alters the API for crypto/elliptic to permit different
implementations in the future. This will allow us to add faster,
constant-time implementations of the standard curves without any more
API changes.

As a demonstration, it also adds a constant-time implementation of
P224. Since it's only 32-bit, it's actually only about 40% the speed
of the generic code on a 64-bit system.

R=r, rsc
CC=golang-dev
https://golang.org/cl/5528088

TestNonStandardNormalValues runs 1.5s,
the change reduces it to 0.2s in short mode.
The problem is with slow machines, emulators and dynamic tools.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5540065

Also, disable server-side generation of TOC for commands as they would
only ever show Overview. The JS does a better job (for now).

Fixes #2732.

R=gri, dsymonds
CC=golang-dev
https://golang.org/cl/5558046

elements.

Pass tests10.dat, test 33:
<!DOCTYPE html><svg><desc><svg><ul>a

| <!DOCTYPE html>
| <html>
|   <head>
|   <body>
|     <svg svg>
|       <svg desc>
|         <svg svg>
|         <ul>
|           "a"

Also pass test 34:
<!DOCTYPE html><p><svg><desc><p>

R=andybalholm, dsymonds
CC=golang-dev
https://golang.org/cl/5536048

R=bradfitz
CC=golang-dev
https://golang.org/cl/5558047

Fixes #2440.

R=r, dsymonds
CC=golang-dev
https://golang.org/cl/5559043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5532097

Its need will be addressed in another way by the redesign.

Fixes #2719.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5536062

R=adg
CC=golang-dev
https://golang.org/cl/5545061

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5541064

R=r
CC=golang-dev
https://golang.org/cl/5556051

Fixes #2693

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5557057

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5554058

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5557059

R=golang-dev, dsymonds, adg
CC=golang-dev
https://golang.org/cl/5557058

Fixes #2534

R=golang-dev, dave, alex.brainman
CC=golang-dev
https://golang.org/cl/5554057

Fixes #2718

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/5532095

R=rsc, adg
CC=golang-dev
https://golang.org/cl/5503089

image/draw benchmarks show <1% change for the fast paths.
The slow paths got worse by 1-4%, but they're the slow paths.
I don't care so much about them, and presumably compiler improvements
could claw it back.

IIUC 6g's inlining is enabled by default now.

benchmark                        old ns/op    new ns/op    delta
draw.BenchmarkFillOver             2988384      2999624   +0.38%
draw.BenchmarkFillSrc               153141       153262   +0.08%
draw.BenchmarkCopyOver             2155756      2170831   +0.70%
draw.BenchmarkCopySrc                72591        72646   +0.08%
draw.BenchmarkNRGBAOver            2487372      2491576   +0.17%
draw.BenchmarkNRGBASrc             1361306      1409180   +3.52%
draw.BenchmarkYCbCr                2540712      2562359   +0.85%
draw.BenchmarkGlyphOver            1004879      1023308   +1.83%
draw.BenchmarkRGBA                 8746670      8844455   +1.12%
draw.BenchmarkGenericOver         31860960     32512960   +2.05%
draw.BenchmarkGenericMaskOver     16369060     16435720   +0.41%
draw.BenchmarkGenericSrc          13128540     13127810   -0.01%
draw.BenchmarkGenericMaskSrc      30059300     28883210   -3.91%

R=r, gri
CC=golang-dev, rsc
https://golang.org/cl/5536059

It works with NewTicker too, but is potentially a bit less efficient,
and reads wrong.

This is what happens when you TBR Windows changes, I guess.

R=golang-dev, gri, iant
CC=golang-dev
https://golang.org/cl/5536060