image/png: fix error message to not return width twice

Fixes issue 5413

R=golang-dev, dave, adg
CC=golang-dev
https://codereview.appspot.com/9153045
C: add Jeremiah Harmsen (Google CLA)

R=golang-dev, bradfitz
CC=golang-dev
https://codereview.appspot.com/9229043
go/doc/example: Fix bug causing false negatives for Example playability.

Allows Examples with KeyValue expressions to be playable in godoc.

During the traversal of the abstract syntax tree any KeyValueExpr Key.Name was incorrectly being added as an unresolved identifier.
Since this identifier could not be provided the Example was marked as unplayable.
This updates the AST traversal to skip Keys (but continue traversing the Values).

Example of problematic AST now fixed (see L99 where "UpperBound" was being added as a missing identifier):

 81  .  .  .  .  .  .  .  .  .  Values: []ast.Expr (len = 1) {
 82  .  .  .  .  .  .  .  .  .  .  0: *ast.UnaryExpr {
 83  .  .  .  .  .  .  .  .  .  .  .  OpPos: 12:19
 84  .  .  .  .  .  .  .  .  .  .  .  Op: &
 85  .  .  .  .  .  .  .  .  .  .  .  X: *ast.CompositeLit {
 86  .  .  .  .  .  .  .  .  .  .  .  .  Type: *ast.SelectorExpr {
 87  .  .  .  .  .  .  .  .  .  .  .  .  .  X: *ast.Ident {
 88  .  .  .  .  .  .  .  .  .  .  .  .  .  .  NamePos: 12:20
 89  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Name: "t_proto"
 90  .  .  .  .  .  .  .  .  .  .  .  .  .  }
 91  .  .  .  .  .  .  .  .  .  .  .  .  .  Sel: *ast.Ident {
 92  .  .  .  .  .  .  .  .  .  .  .  .  .  .  NamePos: 12:41
 93  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Name: "BConfig"
 94  .  .  .  .  .  .  .  .  .  .  .  .  .  }
 95  .  .  .  .  .  .  .  .  .  .  .  .  }
 96  .  .  .  .  .  .  .  .  .  .  .  .  Lbrace: 12:79
 97  .  .  .  .  .  .  .  .  .  .  .  .  Elts: []ast.Expr (len = 2) {
 98  .  .  .  .  .  .  .  .  .  .  .  .  .  0: *ast.KeyValueExpr {
 99  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Key: *ast.Ident {
100  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  NamePos: 13:3
101  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Name: "UpperBound"
102  .  .  .  .  .  .  .  .  .  .  .  .  .  .  }
103  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Colon: 13:13
104  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Value: *ast.CallExpr {
105  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Fun: *ast.SelectorExpr {
106  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  X: *ast.Ident {
107  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  NamePos: 13:15
108  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Name: "proto"
109  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  }
110  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Sel: *ast.Ident {
111  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  NamePos: 13:21
112  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  Name: "Float32"
113  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  }

R=adg
CC=gobot, golang-dev, gri
https://codereview.appspot.com/8569045

Committer: Andrew Gerrand <adg@golang.org>
syscall: fix prototype of Fchflags (API change)
API change, but the old API is obviously wrong.

R=golang-dev, iant, r, rsc
CC=golang-dev
https://codereview.appspot.com/9157044
doc: add FAQ entry about language changes

R=golang-dev, dsymonds, r
CC=golang-dev
https://codereview.appspot.com/9244043
database/sql: remove an unused field from Rows

Found while debugging memory usage. Nobody accesses this field
anymore.

R=golang-dev, i.caught.air, adg, r
CC=golang-dev
https://codereview.appspot.com/9108043
runtime: reduce max arena size on windows/amd64 to 32 GiB
Update issue 5236
Update issue 5402
This CL reduces gofmt's committed memory from 545864 KiB to 139568 KiB.
Note: Go 1.0.3 uses about 70MiB.

R=golang-dev, r, iant, nightlyone
CC=golang-dev
https://codereview.appspot.com/9245043
runtime: fix crash in badsignal()
The linker can generate split stack prolog when a textflag 7 function
makes an indirect function call.  If it happens, badsignal() crashes
trying to dereference g.
Fixes issue 5337.

R=bradfitz, dave, adg, iant, r, minux.ma
CC=adonovan, golang-dev
https://codereview.appspot.com/9226043

Committer: Ian Lance Taylor <iant@golang.org>
api: add go1.1.txt; update cmd/api to use it

R=golang-dev, adg, r
CC=golang-dev
https://codereview.appspot.com/9250043
tag go1.1rc2
Merge branch 'master' into gitfix