Redo "special-case ListMixin.setRange from same list"

Redo "special-case ListMixin.setRange from same list"

This simply reapplies
https://github.com/dart-lang/sdk/commit/001ce2aad76bf0a4af12bfa5159812c56b8cce49

R=lrn@google.com

BUG=

Committed: https://github.com/dart-lang/sdk/commit/20680805d3bd68ca3ae820d40f9ce80b06d6909c

[sra1, 2017-06-28 17:01:04]

Description was changed from

==========
Redo "special-case ListMixin.setRange from same list"

This simply reapplies
https://github.com/dart-lang/sdk/commit/001ce2aad76bf0a4af12bfa5159812c56b8cce49

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

to

==========
Redo "special-case ListMixin.setRange from same list"

This simply reapplies
https://github.com/dart-lang/sdk/commit/001ce2aad76bf0a4af12bfa5159812c56b8cce49

TBR=lrn@google.com

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

[sra1, 2017-06-28 17:01:04]

sra@google.com changed reviewers:
+ lrn@google.com

[Lasse Reichstein Nielsen, 2017-07-10 09:27:09]

lgtm

[sra1, 2017-07-15 18:21:50]

Description was changed from

==========
Redo "special-case ListMixin.setRange from same list"

This simply reapplies
https://github.com/dart-lang/sdk/commit/001ce2aad76bf0a4af12bfa5159812c56b8cce49

TBR=lrn@google.com

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

to

==========
Redo "special-case ListMixin.setRange from same list"

This simply reapplies
https://github.com/dart-lang/sdk/commit/001ce2aad76bf0a4af12bfa5159812c56b8cce49

R=lrn@google.com

BUG=

Committed:
https://github.com/dart-lang/sdk/commit/20680805d3bd68ca3ae820d40f9ce80b06d6909c
==========

[sra1, 2017-07-15 18:21:51]

Committed patchset #1 (id:1) manually as
20680805d3bd68ca3ae820d40f9ce80b06d6909c (presubmit successful).