Updates #16937

Change-Id: I6d1b210c741269b58040bd68bf3b51644f891737
Reviewed-on: https://go-review.googlesource.com/28487
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

The ctxt parameter is always set to 0 on entry into anylit so make this
parameter a literal constant, and where possibly remove ctxt as a parameter
where it is known to be a constant zero.

Passes toolstash -cmp.

This is a re-creation of CL 28221 by Dave Cheney.
That CL was graciously reverted in CL 28480
to make merging other CLs easier.

Change-Id: If7a57bf0e27774d9890adbc30af9fabb4aff1058
Reviewed-on: https://go-review.googlesource.com/28483
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>

Fixes #16886

Change-Id: Idfacb0cf44d9994559c8e09032b4595887e76433
Reviewed-on: https://go-review.googlesource.com/28214Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
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Found by vet.

Change-Id: I09b79d68c7a5fc97e0edda4700a82bfbb00a4f45
Reviewed-on: https://go-review.googlesource.com/28486
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>

Add docs.
Give it a more natural signature.

Passes toolstash -cmp.

Change-Id: Iab368dd10e8f16e41b725c2980020bbead2cdefb
Reviewed-on: https://go-review.googlesource.com/26756
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

No functional changes. Passes toolstash -cmp.

Change-Id: I1ad467e574fd2ea80ab1459c0c943d9ff66c23ec
Reviewed-on: https://go-review.googlesource.com/26755
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>

They were almost identical.
Merge them and some of their calling code.

Passes toolstash -cmp.

Change-Id: I9e92a864a6c09c9e18ed52dc247a678467e344ba
Reviewed-on: https://go-review.googlesource.com/26754
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>

Does not pass toolstash -cmp due to changed export data,
but the cmd/go binary (which doesn't contain export data)
is bit-for-bit identical.

Change-Id: I6b12f9de18cf7da528e9207dccbf8f08c969f142
Reviewed-on: https://go-review.googlesource.com/26753
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
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Reviewed-by: David Crawshaw <crawshaw@golang.org>

Reduce the duplication in every arch by moving the code into package gc.

Change-Id: Ia111add8316492571825431ecd4f0154c8792ae1
Reviewed-on: https://go-review.googlesource.com/28481
Run-TryBot: Michael Pratt <mpratt@google.com>
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Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Fixes #16068

Change-Id: I04e80a181c0b7356996f7a1158ea4895ff9e1e39
Reviewed-on: https://go-review.googlesource.com/28477
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Revert to make josharians branch land cleanly

This reverts commit 38abd43b.

Change-Id: Idde1df953baf6e5742c87c4edd4bee0b6b418aca
Reviewed-on: https://go-review.googlesource.com/28480
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This custom version is identical to CheckLoweredPhi. The addition of
CheckLoweredPhi likely raced with adding PPC64.

Change-Id: I294dcb758d312e93fb8842f4d1e12bf0f63a1e06
Reviewed-on: https://go-review.googlesource.com/28479
Run-TryBot: Michael Pratt <mpratt@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #16980

Change-Id: I902a02b157c2c7d1772f5122b850dc48b1d7a224
Reviewed-on: https://go-review.googlesource.com/28474Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

It was fixed earlier in the Go 1.8 cycle.
Add a test.

Fixes #15895

Change-Id: I5834831235d99b9fcf21b435932cdd7ac6dc2c6e
Reviewed-on: https://go-review.googlesource.com/28476
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
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Provide bounds elim hints in EncodeRune.

name                  old time/op  new time/op  delta
EncodeASCIIRune-4     2.69ns ± 2%  2.69ns ± 2%    ~     (p=0.193 n=47+46)
EncodeJapaneseRune-4  5.97ns ± 2%  5.38ns ± 2%  -9.93%  (p=0.000 n=49+50)

Change-Id: I1a6dcffff3bdd64ab93c2130021e3b00981de4c8
Reviewed-on: https://go-review.googlesource.com/28492Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The ctxt parameter is always set to 0 on entry into anylit so make this
parameter a literal constant, and where possibly remove ctxt as a parameter
where it is known to be a constant zero.

Change-Id: I3e76e06456d7b1a1ea875ffeb2efefa4a1ff5a7e
Reviewed-on: https://go-review.googlesource.com/28221
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The http.Transport's retry can't retry requests with non-nil
bodies. When cloning an incoming server request into an outgoing
client request, nil out the Body field if the ContentLength is 0. (For
server requests, Body is always non-nil, even for GET, HEAD, etc.)

Also, don't use the deprecated CancelRequest and use Context instead.

And don't set Proto, ProtoMajor, ProtoMinor. Those are ignored in
client requests, which was probably a later documentation
clarification.

Fixes #16036
Updates #16696 (remove useless Proto lines)

Change-Id: I70a869e9bd4bf240c5838e82fb5aa695a539b343
Reviewed-on: https://go-review.googlesource.com/28412
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>

The use of PAX headers can modify the overall file size, thus the
formerly created regFileReader may be stale.

The relevant PAX specification for this behavior is:
<<<
Any fields in the preceding optional extended header shall override
the associated fields in this header block for this file.
>>>
Where "optional extended header" refers to the preceding PAX header.
Where "this header block" refers to the subsequent USTAR header.

Fixes #15573
Fixes #15564

Change-Id: I83b1c3f05a9ca2d3be38647425ad21a9fe450ee2
Reviewed-on: https://go-review.googlesource.com/28418Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Follow-up to https://go-review.googlesource.com/28394.

Change-Id: Ic4147e9ae786a4de0a3454131fac03e940ae2e76
Reviewed-on: https://go-review.googlesource.com/28417Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Change-Id: I242a8960583e333f372929aad4adb8efbe441cd4
Reviewed-on: https://go-review.googlesource.com/28413Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Jaana Burcu Dogan <jbd@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

hbits.morePointers and hbits.isPointer both
do a load and a shift. Do it only once.

Benchmarks using compilebench (because it is
the benchmark I have the most tooling around),
on a quiet machine.

name       old time/op      new time/op      delta
Template        291ms ±14%       290ms ±15%    ~          (p=0.702 n=100+99)
Unicode         143ms ± 9%       142ms ± 9%    ~           (p=0.126 n=99+98)
GoTypes         934ms ± 4%       933ms ± 4%    ~         (p=0.937 n=100+100)
Compiler        4.92s ± 2%       4.90s ± 1%  -0.28%        (p=0.003 n=98+98)

name       old user-ns/op   new user-ns/op   delta
Template   360user-ms ± 5%  355user-ms ± 4%  -1.37%        (p=0.000 n=97+96)
Unicode    178user-ms ± 6%  176user-ms ± 6%  -1.24%        (p=0.001 n=96+99)
GoTypes    1.22user-s ± 5%  1.21user-s ± 5%  -0.94%      (p=0.000 n=100+100)
Compiler   6.50user-s ± 2%  6.44user-s ± 3%  -0.94%        (p=0.000 n=96+98)

On amd64, before:

"".scanobject t=1 size=581 args=0x10 locals=0x78

After:

"".scanobject t=1 size=540 args=0x10 locals=0x78


Change-Id: I420ac3704549d484a5d85e19fea82c85da389514
Reviewed-on: https://go-review.googlesource.com/22712
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Austin Clements <austin@google.com>
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We reset global buffer only if its pos != 0.
We ought to do it always, but queue it only if pos != 0.
This is a latent bug. Currently it does not fire because
whenever we create a global buffer, we increment pos.

Change-Id: I01e28ae88ce9a5412497c524391b8b7cb443ffd9
Reviewed-on: https://go-review.googlesource.com/25574
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Rename variable to bitScan according to
TODO comment.

Change-Id: I81dd8cc1ca28c0dc9308a654ad65cdf5b2fd2ce3
Reviewed-on: https://go-review.googlesource.com/25175
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

Currently this message says "invalid stack pointer", which could be
interpreted as the value of SP being invalid. Change it to "invalid
pointer found on stack" to emphasize that it's a pointer on the stack
that's invalid.

Updates #16948.

Change-Id: I753624f8cc7e08cf13d3ea5d9c790cc4af9fa372
Reviewed-on: https://go-review.googlesource.com/28430
Run-TryBot: Austin Clements <austin@google.com>
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

The maximum input plaintext for GCM is 64GiB - 64. Since the GCM
interface is one-shot, it's very hard to hit this in Go (one would need
a 64GiB buffer in memory), but we should still enforce this limit.

Thanks to Quan Nguyen for pointing it out.

Change-Id: Icced47bf8d4d5dfbefa165cf13e893205c9577b8
Reviewed-on: https://go-review.googlesource.com/28410
Run-TryBot: Adam Langley <agl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>

RFC 2616, section 14.10 says:

>>>
HTTP/1.1 proxies MUST parse the Connection header field before a message
is forwarded and, for each connection-token in this field, remove any
header field(s) from the message with the same name as the
connection-token. Connection options are signaled by the presence of a
connection-token in the Connection header field, not by any
corresponding additional header field(s), since the additional header
field may not be sent if there are no parameters associated with that
connection option.
<<<

The same requirement was included in RFC 7230, section 6.1.

Fixes #16875

Change-Id: I57ad4a4a17775537c8810d0edd7de1604317b5fa
Reviewed-on: https://go-review.googlesource.com/27970Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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While it was previously explicitly documented that "the default Source"
is safe for concurrent use, a careless reader can interpret that as
meaning "the implementation of the Source interface created by functions
in this package" rather than "the default shared Source used by
top-level functions". Be explicit that the Source returned by NewSource
is not safe for use by multiple goroutines.

Fixes #3611.

Change-Id: Iae4bc04c3887ad6e2491e36e38feda40324022c5
Reviewed-on: https://go-review.googlesource.com/25501Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Current banners are:

##### Building Go bootstrap tool.
##### Building Go toolchain using /Users/josh/go/1.4.
##### Building go_bootstrap for host, darwin/amd64.
##### Building packages and commands for darwin/amd64.
##### Testing packages.
##### GOMAXPROCS=2 runtime -cpu=1,2,4
##### Testing without libgcc.
##### sync -cpu=10
##### ../misc/cgo/stdio
##### ../misc/cgo/life
##### ../misc/cgo/fortran
##### ../misc/cgo/test
##### Testing race detector
##### ../misc/cgo/testso
##### ../misc/cgo/testsovar
##### misc/cgo/testcarchive
##### ../misc/cgo/testcshared
##### ../misc/cgo/errors
##### ../test/bench/go1
##### ../test
##### API check

One of these things is not like the others.
Fix that.

Change-Id: If0bd8ea9293d73b5d1b70d6bf676bd9192991505
Reviewed-on: https://go-review.googlesource.com/26759
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #16565

Change-Id: I3edfd2576a7ca5270644a4e7f126854f821f2c9a
Reviewed-on: https://go-review.googlesource.com/25385Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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Per RFC 7230, Section 3.3.2: "A server MUST NOT send a Content-Length
header field in any response with a status code of 1xx (Informational)
or 204 (No Content).".

Fixes #16942

Change-Id: I8006c76c126304e13618966e6eafb08a3885d3cd
Reviewed-on: https://go-review.googlesource.com/28351Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

make(T, n, m) returns a slice of type T with length n and capacity m
where "The size arguments n and m must be of integer type or untyped."
https://tip.golang.org/ref/spec#Making_slices_maps_and_channels

The failure to reject typed non-integer size arguments in make
during compile time was uncovered after https://golang.org/cl/27851
changed the generation of makeslice calls.

Fixes   #16940
Updates #16949

Change-Id: Ib1e3576f0e6ad199c9b16b7a50c2db81290c63b4
Reviewed-on: https://go-review.googlesource.com/28301Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Found by vet.

Change-Id: I50420771678b1a3695348ce1a81f410479ed09a1
Reviewed-on: https://go-review.googlesource.com/28394
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #15509

Change-Id: I44073533f02d38795f9ba9b255db4d1ee426d70e
Reviewed-on: https://go-review.googlesource.com/28390
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Update #16141

Change-Id: I7d32c5cdc197d86491a67ea579fa16cb3d675b51
Reviewed-on: https://go-review.googlesource.com/28273
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

Change-Id: I63af8f0a19ec91f4a2001aa7a2eadcd2232a47df
Reviewed-on: https://go-review.googlesource.com/28348Reviewed-by: Ian Lance Taylor <iant@golang.org>

name                     old time/op    new time/op      delta
IndexByte32-48             9.05ns ± 7%      9.59ns ±11%     +5.93%  (p=0.001 n=19+20)
IndexByte4K-48              118ns ± 4%       122ns ± 8%     +3.52%  (p=0.002 n=19+19)
IndexByte4M-48              172µs ±13%       188µs ±12%     +9.49%  (p=0.000 n=20+20)
IndexByte64M-48            8.00ms ±14%      8.05ms ±23%       ~     (p=0.799 n=20+20)
IndexBytePortable32-48     41.7ns ±15%      42.5ns ±12%       ~     (p=0.372 n=20+20)
IndexBytePortable4K-48     3.08µs ±16%      3.26µs ±10%     +5.77%  (p=0.018 n=20+20)
IndexBytePortable4M-48     3.12ms ±17%      3.20ms ±10%       ~     (p=0.157 n=20+20)
IndexBytePortable64M-48    54.0ms ±14%      55.3ms ±14%       ~     (p=0.640 n=20+20)
Index32-48                  230ns ±12%        46ns ± 6%    -79.87%  (p=0.000 n=20+19)
Index4K-48                 43.2µs ± 9%       3.2µs ±12%    -92.58%  (p=0.000 n=19+20)
Index4M-48                 44.4ms ± 7%       3.3ms ±13%    -92.59%  (p=0.000 n=19+20)
Index64M-48                 714ms ±10%        56ms ± 8%    -92.22%  (p=0.000 n=19+19)
IndexEasy32-48             52.7ns ±10%      31.0ns ±11%    -41.21%  (p=0.000 n=20+20)
IndexEasy4K-48              139ns ± 5%      1598ns ± 6%  +1046.37%  (p=0.000 n=19+19)
IndexEasy4M-48              179µs ± 8%      1674µs ±10%   +834.31%  (p=0.000 n=19+20)
IndexEasy64M-48            8.56ms ±10%     27.82ms ±16%   +225.14%  (p=0.000 n=19+20)

name                     old speed      new speed        delta
IndexByte32-48           3.52GB/s ± 7%    3.35GB/s ±11%     -4.99%  (p=0.001 n=20+20)
IndexByte4K-48           34.5GB/s ± 7%    33.2GB/s ±10%     -3.67%  (p=0.002 n=20+20)
IndexByte4M-48           24.6GB/s ±14%    22.4GB/s ±14%     -8.73%  (p=0.000 n=20+20)
IndexByte64M-48          8.42GB/s ±16%    8.42GB/s ±19%       ~     (p=0.799 n=20+20)
IndexBytePortable32-48    770MB/s ±13%     756MB/s ±11%       ~     (p=0.383 n=20+20)
IndexBytePortable4K-48   1.34GB/s ±14%    1.26GB/s ±10%     -5.76%  (p=0.018 n=20+20)
IndexBytePortable4M-48   1.35GB/s ±15%    1.31GB/s ±11%       ~     (p=0.157 n=20+20)
IndexBytePortable64M-48  1.25GB/s ±16%    1.22GB/s ±13%       ~     (p=0.640 n=20+20)
Index32-48                138MB/s ± 8%     687MB/s ± 8%   +398.57%  (p=0.000 n=19+20)
Index4K-48               94.9MB/s ± 9%  1280.5MB/s ±11%  +1249.11%  (p=0.000 n=19+20)
Index4M-48               94.6MB/s ± 7%  1278.5MB/s ±12%  +1250.99%  (p=0.000 n=19+20)
Index64M-48              94.2MB/s ±10%  1210.9MB/s ± 8%  +1185.04%  (p=0.000 n=19+19)
IndexEasy32-48            608MB/s ±10%    1035MB/s ±10%    +70.15%  (p=0.000 n=20+20)
IndexEasy4K-48           29.3GB/s ± 6%     2.6GB/s ± 6%    -91.24%  (p=0.000 n=19+19)
IndexEasy4M-48           23.3GB/s ±10%     2.5GB/s ± 9%    -89.23%  (p=0.000 n=20+20)
IndexEasy64M-48          7.86GB/s ±11%    2.42GB/s ±14%    -69.18%  (p=0.000 n=19+20)

Change-Id: Ia191f0a6ca80e113397d9ed98d25f195768b65bc
Reviewed-on: https://go-review.googlesource.com/22550
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

Intrinsified atomic op produces <value,memory>. Make sure this
memory is considered in the store chain calculation.

Fixes #16948.

Change-Id: I029f164b123a7e830214297f8373f06ea0bf1e26
Reviewed-on: https://go-review.googlesource.com/28350
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

See the issue below for details.

Fixes #16794.

Change-Id: I7e338089fd80ddcb634fa80bfc658dee2772361c
Reviewed-on: https://go-review.googlesource.com/27356Reviewed-by: Ian Lance Taylor <iant@golang.org>

In Go 1.0, the Config struct consisted only of exported fields.

In Go 1.1, it started to grow private, uncopyable fields (sync.Once,
sync.Mutex, etc).

Ever since, people have been writing their own private Config.Clone
methods, or risking it and doing a language-level shallow copy and
copying the unexported sync variables.

Clean this up and export the Config.clone method as Config.Clone.
This matches the convention of Template.Clone from text/template and
html/template at least.

Fixes #15771
Updates #16228 (needs update in x/net/http2 before fixed)
Updates #16492 (not sure whether @agl wants to do more)

Change-Id: I48c2825d4fef55a75d2f99640a7079c56fce39ca
Reviewed-on: https://go-review.googlesource.com/28075
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>

The tar.Reader guarantees stickiness of errors. Ensuring this property means
that the methods of Reader need to be consistent about whose responsibility it
is to actually ensure that errors are sticky.

In this CL, we make it only the responsibility of the exported methods
(Next and Read) to store tr.err. All other methods just return the error as is.

As part of this change, we also check the error value of mergePAX (and test
that it properly detects invalid PAX files). Since the value of mergePAX was
never used before, we change it such that it always returns ErrHeader instead
of strconv.SyntaxError. This keeps it consistent with other usages of strconv
in the same tar package.

Change-Id: Ia1c31da71f1de4c175da89a385dec665d3edd167
Reviewed-on: https://go-review.googlesource.com/28215
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>