Refactored treatment of closure variables in dart2js CPS.

Refactored treatment of closure variables in dart2js CPS.

Closure variables are now represented by a ClosureVariable object.
Previously they were identified by a LocalElement.

Parameters to a FunctionDefinition are now a mix of Parameter and
ClosureVariable. FunctionDefinitions also have a list of all the closure
variables they declare.

This change is a step toward supporting field initializers that modify or
capture function parameters.

BUG=
R=johnniwinther@google.com, sigurdm@google.com

Committed: https://code.google.com/p/dart/source/detail?r=42164

[asgerf, 2014-12-05 13:14:50]

asgerf@google.com changed reviewers:
+ johnniwinther@google.com, sigurdm@google.com

[Johnni Winther, 2014-12-08 13:15:13]

lgtm

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/cps_ir/...
File pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart (right):

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/cps_ir/...
pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart:184: final Map<Local,
ir.ClosureVariable> local2closure =
Document the members.

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/cps_ir/...
pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart:319: ir.ClosureVariable
getClosureVariable(LocalElement element) {
Document this.

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/cps_ir/...
pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart:323: void
createFunctionParameter(ParameterElement parameterElement) {
Ditto.

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/tree_ir...
File pkg/compiler/lib/src/tree_ir/tree_ir_builder.dart (right):

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/tree_ir...
pkg/compiler/lib/src/tree_ir/tree_ir_builder.dart:79: Variable variable =
local2closure[irVariable];
This could be rewritten as a putIfAbsent.

[sigurdm, 2014-12-08 13:23:39]

lgtm

[asgerf, 2014-12-08 13:44:00]

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/cps_ir/...
File pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart (right):

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/cps_ir/...
pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart:184: final Map<Local,
ir.ClosureVariable> local2closure =
On 2014/12/08 13:15:13, Johnni Winther wrote:
> Document the members.

Done.

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/cps_ir/...
pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart:319: ir.ClosureVariable
getClosureVariable(LocalElement element) {
On 2014/12/08 13:15:13, Johnni Winther wrote:
> Document this.

Done.

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/cps_ir/...
pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart:323: void
createFunctionParameter(ParameterElement parameterElement) {
On 2014/12/08 13:15:13, Johnni Winther wrote:
> Ditto.

Done.

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/tree_ir...
File pkg/compiler/lib/src/tree_ir/tree_ir_builder.dart (right):

https://codereview.chromium.org/756383004/diff/1/pkg/compiler/lib/src/tree_ir...
pkg/compiler/lib/src/tree_ir/tree_ir_builder.dart:79: Variable variable =
local2closure[irVariable];
On 2014/12/08 13:15:13, Johnni Winther wrote:
> This could be rewritten as a putIfAbsent.

Done.

[asgerf, 2014-12-08 14:06:50]

Committed patchset #2 (id:20001) manually as 42164 (presubmit successful).