Support backtrace debug command when stack is empty

Support backtrace debug command when stack is empty

Committed: http://code.google.com/p/v8/source/detail?r=3663

[Peter Rybin, 2010-01-16 23:44:41]

Hi Søren

I'd like to support "suspend" command when in Debug::ProcessDebugMessages, i.e.
when stack is empty.
It seems that I only need to disable one error dianostic.

Peter

[Søren Thygesen Gjesse, 2010-01-18 10:09:56]

LGTM

Please add a test sending a backtrace request with an empty stack.

[Peter Rybin, 2010-01-19 22:41:28]

On 2010/01/18 10:09:56, Søren Gjesse wrote:
> LGTM
> 
> Please add a test sending a backtrace request with an empty stack.

I added a test and however embarrassing it might sound, I found my change is
unnecessary.

So could you please take a look at the test only.

Peter

[Søren Thygesen Gjesse, 2010-01-20 09:44:36]

LGTM

http://codereview.chromium.org/536089/diff/8001/4002
File test/cctest/test-debug.cc (right):

http://codereview.chromium.org/536089/diff/8001/4002#newcode5874
test/cctest/test-debug.cc:5874: BracktraceData::frame_counter = -10;
Why not just -1?

[Peter Rybin, 2010-01-20 16:32:24]

http://codereview.chromium.org/536089/diff/8001/4002
File test/cctest/test-debug.cc (right):

http://codereview.chromium.org/536089/diff/8001/4002#newcode5874
test/cctest/test-debug.cc:5874: BracktraceData::frame_counter = -10;
On 2010/01/20 09:44:36, Søren Gjesse wrote:
> Why not just -1?

I expect atoi to return "-1" if number wasn't parsed. So I to put different
magic number here (i.e. -10).