PPC: Handle the case when derived constructor is [[Call]]ed with 0 args.

PPC: Handle the case when derived constructor is [[Call]]ed with 0 args.

Port cf53fed972896bf23c037ce7ac9f8e1512463c62

Original commit message:
ArgumentsAdaptorStub for derived constructor (the one that needs
new.target) works in this way:
 - If the constructor is invoked via the Construct stub, we know that
   actual arguments always include new.target. ``arguments`` object
   however should not include a new.target, therefore we remove it.
   We achieve this by decrementing the argument count.
 - If the constructor is invoked as a call, we do not care for a correct
   ``arguments`` array since the constructor will immediately throw on
   entrance.
The bug is that the call could actually pass 0 actual arguments, but I
decrement unconditionally :(. The fix is to detect this case and avoid
decrementing. ``arguments`` is bogus, but it is ok as constructor
throws.

Long-term we should just remove mucking about with arguments for
new.target and just get it from the stack.

R=dslomov@chromium.org, dstence@us.ibm.com, michael_dawson@ca.ibm.com
BUG=

Committed: https://crrev.com/c7e02041b0bcc5c492d8129f2a6dac848299ddc2
Cr-Commit-Position: refs/heads/master@{#28269}

[dstence, 2015-05-06 15:49:28]

lgtm

[MTBrandyberry, 2015-05-06 15:51:23]

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

[commit-bot: I haz the power, 2015-05-06 15:51:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1125223002/1

[Dmitry Lomov (no reviews), 2015-05-06 16:09:23]

lgtm

[commit-bot: I haz the power, 2015-05-06 16:14:06]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-05-06 16:14:22]

Patchset 1 (id:??) landed as
https://crrev.com/c7e02041b0bcc5c492d8129f2a6dac848299ddc2
Cr-Commit-Position: refs/heads/master@{#28269}