Port db2ba190

Original commit message:
    The semantics of the %_CallFunction intrinsic seem to be very unclear,
    which resulted in a lot of bugs. Especially the combination with
    %IsSloppyModeFunction is always a bug, because the receiver would be
    wrapped in the wrong context. So the %IsSloppyModeFunction helper is
    gone now, and many of the buggy uses of %_CallFunction are also
    eliminated.

    If you ever need to call something with a different receiver, then
    %_Call is your friend now. It does what you want and implements the
    call sequence fully (and correct).

R=bmeurer@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, dstence@us.ibm.com
BUG=v8:4413
LOG=n

Review URL: https://codereview.chromium.org/1310303008

Cr-Commit-Position: refs/heads/master@{#30655}