Removes checks for stack overflow from arm and mips simulators

Removes checks for stack overflow from arm and mips simulators

The checks were performed before runtime and native calls,
but if we abort on an assertion failure there, then we
never make it to the StackOverflow runtime call.

R=regis@google.com

Committed: https://code.google.com/p/dart/source/detail?r=24979

[regis, 2013-07-12 22:23:56]

LGTM

tricky :-)

[zra, 2013-07-12 23:06:30]

Committed patchset #1 manually as r24979 (presubmit successful).