Add Dart code to diff_view

Add Dart code to diff_view

+ update annotations to make nodes without information more visible
+ add annotation for unused source information
+ use source information from subnodes in variable declarations, assignments and expression statements (a fix triggered by showing unused information)
+ support source information for initial variable declarations
+ new source info is now comparable to the old; need to check source locations before  switch to the new

R=sigmund@google.com

Committed: https://github.com/dart-lang/sdk/commit/1a4ba676adf92700e3964aa29276b4bab4d108ee

[Johnni Winther, 2016-02-08 14:04:34]

Description was changed from

==========
Add Dart code to diff_view

BUG=
==========

to

==========
Add Dart code to diff_view

+ update annotations to make nodes without information more visible
+ add annotation for unused source information
+ use source information from subnodes in variable declarations, assignments and
expression statements (a fix triggered by showing unused information)
+ support source information for initial variable declarations
+ new source info is now comparable to the old; need to check source locations
before  switch to the new
==========

[Johnni Winther, 2016-02-08 14:05:04]

johnniwinther@google.com changed reviewers:
+ sigmund@google.com

[Siggi Cherem (dart-lang), 2016-02-08 22:31:53]

lgtm, just a question below

https://codereview.chromium.org/1678043003/diff/20001/pkg/compiler/lib/src/io...
File pkg/compiler/lib/src/io/position_information.dart (right):

https://codereview.chromium.org/1678043003/diff/20001/pkg/compiler/lib/src/io...
pkg/compiler/lib/src/io/position_information.dart:252: if (functionExpression !=
null) {
nit: I'd remove the call to `asFunctionExpression` method, and simply do an
instance check here. Then we get advantage of the type strengthening in branches
without having to add explicit typed variables:

if (node is FunctionExpression) {
  return buildBegin(node.body);
} else if (element is FieldElement && element.initializer != null) {
  return buildBegin(element.initializer);
}

https://codereview.chromium.org/1678043003/diff/20001/tests/compiler/dart2js/...
File tests/compiler/dart2js/sourcemaps/diff_view.dart (right):

https://codereview.chromium.org/1678043003/diff/20001/tests/compiler/dart2js/...
tests/compiler/dart2js/sourcemaps/diff_view.dart:300: offset with unused source
information
not sure what's the distinction here between additional/unneeded/unused

Aren't both unneeded? Is "additional" refering to the old source-maps, while
"unused" to the new source-maps?

[Johnni Winther, 2016-02-09 10:25:41]

Description was changed from

==========
Add Dart code to diff_view

+ update annotations to make nodes without information more visible
+ add annotation for unused source information
+ use source information from subnodes in variable declarations, assignments and
expression statements (a fix triggered by showing unused information)
+ support source information for initial variable declarations
+ new source info is now comparable to the old; need to check source locations
before  switch to the new
==========

to

==========
Add Dart code to diff_view

+ update annotations to make nodes without information more visible
+ add annotation for unused source information
+ use source information from subnodes in variable declarations, assignments and
expression statements (a fix triggered by showing unused information)
+ support source information for initial variable declarations
+ new source info is now comparable to the old; need to check source locations
before  switch to the new

R=sigmund@google.com

Committed:
https://github.com/dart-lang/sdk/commit/1a4ba676adf92700e3964aa29276b4bab4d108ee
==========

[Johnni Winther, 2016-02-09 10:25:43]

Committed patchset #4 (id:60001) manually as
1a4ba676adf92700e3964aa29276b4bab4d108ee (presubmit successful).

[Johnni Winther, 2016-02-10 09:19:27]

https://codereview.chromium.org/1678043003/diff/20001/pkg/compiler/lib/src/io...
File pkg/compiler/lib/src/io/position_information.dart (right):

https://codereview.chromium.org/1678043003/diff/20001/pkg/compiler/lib/src/io...
pkg/compiler/lib/src/io/position_information.dart:252: if (functionExpression !=
null) {
On 2016/02/08 22:31:53, Siggi Cherem (dart-lang) wrote:
> nit: I'd remove the call to `asFunctionExpression` method, and simply do an
> instance check here. Then we get advantage of the type strengthening in
branches
> without having to add explicit typed variables:
> 
> if (node is FunctionExpression) {
>   return buildBegin(node.body);
> } else if (element is FieldElement && element.initializer != null) {
>   return buildBegin(element.initializer);
> }

Done for FunctionExpression. Type promotion is not strong enough to handle the
latter case.

https://codereview.chromium.org/1678043003/diff/20001/tests/compiler/dart2js/...
File tests/compiler/dart2js/sourcemaps/diff_view.dart (right):

https://codereview.chromium.org/1678043003/diff/20001/tests/compiler/dart2js/...
tests/compiler/dart2js/sourcemaps/diff_view.dart:300: offset with unused source
information
On 2016/02/08 22:31:53, Siggi Cherem (dart-lang) wrote:
> not sure what's the distinction here between additional/unneeded/unused
> 
> Aren't both unneeded? Is "additional" refering to the old source-maps, while
> "unused" to the new source-maps?

Large description added in hovertext.

[Siggi Cherem (dart-lang), 2016-02-10 16:28:28]

thanks! lgtm