PPC: [es6] Tail calls support.

PPC: [es6] Tail calls support.

Port 6131ab1edd6e78be01ac90b8f0b0f4f27f308071

Original commit message:
    This CL implements PrepareForTailCall() mentioned in ES6 spec for full codegen, Crankshaft and Turbofan.
    When debugger is active tail calls are disabled.

    Tail calling can be enabled by --harmony-tailcalls flag.

R=ishell@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=v8:4698
LOG=Y

Committed: https://crrev.com/95aedaa0c853749649c257fdf7b50cfe5be0eda4
Cr-Commit-Position: refs/heads/master@{#33524}

[Igor Sheludko, 2016-01-26 16:34:51]

lgtm

[MTBrandyberry, 2016-01-26 16:38:12]

The CQ bit was checked by mbrandy@us.ibm.com

[commit-bot: I haz the power, 2016-01-26 16:38:23]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1635823003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1635823003/1

[commit-bot: I haz the power, 2016-01-26 16:58:01]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-01-26 16:58:41]

Description was changed from

==========
PPC: [es6] Tail calls support.

Port 6131ab1edd6e78be01ac90b8f0b0f4f27f308071

Original commit message:
    This CL implements PrepareForTailCall() mentioned in ES6 spec for full
codegen, Crankshaft and Turbofan.
    When debugger is active tail calls are disabled.

    Tail calling can be enabled by --harmony-tailcalls flag.

R=ishell@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com,
michael_dawson@ca.ibm.com
BUG=v8:4698
LOG=Y
==========

to

==========
PPC: [es6] Tail calls support.

Port 6131ab1edd6e78be01ac90b8f0b0f4f27f308071

Original commit message:
    This CL implements PrepareForTailCall() mentioned in ES6 spec for full
codegen, Crankshaft and Turbofan.
    When debugger is active tail calls are disabled.

    Tail calling can be enabled by --harmony-tailcalls flag.

R=ishell@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com,
michael_dawson@ca.ibm.com
BUG=v8:4698
LOG=Y

Committed: https://crrev.com/95aedaa0c853749649c257fdf7b50cfe5be0eda4
Cr-Commit-Position: refs/heads/master@{#33524}
==========

[commit-bot: I haz the power, 2016-01-26 16:58:41]

Patchset 1 (id:??) landed as
https://crrev.com/95aedaa0c853749649c257fdf7b50cfe5be0eda4
Cr-Commit-Position: refs/heads/master@{#33524}