Cleanup the handling of control flow in the toplevel code generator....

Cleanup the handling of control flow in the toplevel code generator.

Do abstract the setting and restoring of 'argument' state into a
function that takes arguments.

Do not set the argument state in the code generator unless it
represents arguments to a recursive call to Visit.


Committed: http://code.google.com/p/v8/source/detail?r=3594

[Kevin Millikin (Chromium), 2010-01-12 09:00:18]

Lasse and/or Bill, do you have time to take a quick look at this?

[Kevin Millikin (Chromium), 2010-01-12 16:13:21]

Florian, do you have time to take a look at this?

[fschneider, 2010-01-12 18:09:39]

LGTM!