Simplified 'return' handling in the instruction selector.

Simplified 'return' handling in the instruction selector.

The RawMachineAssembler now behaves like the rest of TurboFan,
removing the need for some special cases.

Committed: https://crrev.com/8aa7215246bbf56a4f2673897c5dc16c9f0e365d
Cr-Commit-Position: refs/heads/master@{#28028}

[Sven Panne, 2015-04-23 12:09:01]

svenpanne@chromium.org changed reviewers:
+ dcarney@chromium.org

[dcarney, 2015-04-23 12:10:17]

lgtm

[Sven Panne, 2015-04-23 12:14:39]

The CQ bit was checked by svenpanne@chromium.org

[commit-bot: I haz the power, 2015-04-23 12:14:48]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1090393003/1

[commit-bot: I haz the power, 2015-04-23 12:39:41]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-23 12:39:52]

Patchset 1 (id:??) landed as
https://crrev.com/8aa7215246bbf56a4f2673897c5dc16c9f0e365d
Cr-Commit-Position: refs/heads/master@{#28028}