dart2js cps: Bugfix in operator specialization.

dart2js cps: Bugfix in operator specialization.

Binary operators were always replaced with string concatenation if both
operands were strings.

BUG=
R=floitsch@google.com

Committed: https://github.com/dart-lang/sdk/commit/02203937972fcff2c1de832ac02afae38e04b415

[asgerf, 2015-07-06 08:31:39]

asgerf@google.com changed reviewers:
+ floitsch@google.com

[floitsch, 2015-07-06 09:14:12]

LGTM.

[asgerf, 2015-07-06 09:15:07]

Committed patchset #1 (id:1) manually as
02203937972fcff2c1de832ac02afae38e04b415 (presubmit successful).

[karlklose, 2015-07-07 12:48:00]

karlklose@google.com changed reviewers:
+ karlklose@google.com

[karlklose, 2015-07-07 12:48:00]

https://codereview.chromium.org/1210403008/diff/1/pkg/compiler/lib/src/cps_ir...
File pkg/compiler/lib/src/cps_ir/type_propagation.dart (right):

https://codereview.chromium.org/1210403008/diff/1/pkg/compiler/lib/src/cps_ir...
pkg/compiler/lib/src/cps_ir/type_propagation.dart:685: if (node.selector.name ==
'+') {
You could also align this with the structure of the handling of 'operator =='.

https://codereview.chromium.org/1210403008/diff/1/tests/language/string_no_op...
File tests/language/string_no_operator_test.dart (right):

https://codereview.chromium.org/1210403008/diff/1/tests/language/string_no_op...
tests/language/string_no_operator_test.dart:8: var x = "x";
That's a lot of spaces.