[Interpreter] Fixes translation from bailout id to code offset.

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index c4653c61e29f03ba0055841d99b0c862fca280ba..debd3ce69fee04d193c6e05420a5f78557bfa153 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -1013,7 +1013,7 @@ void OptimizedFrame::Summarize(List<FrameSummary>* frames) {
         abstract_code = AbstractCode::cast(code);
       } else {
         DCHECK_EQ(frame_opcode, Translation::INTERPRETED_FRAME);
-        code_offset = bailout_id.ToInt();
+        code_offset = bailout_id.ToInt() - 1;

[mythria, 2016/03/04 16:15:33]

This is not a proper fix, but works. As Yang, pointed out bailout id is the next
instruction and not the current node id. When we subtract 1 we will be at the
last bytecode of the current instruction. Source position returns the same value
if we are at the beginning or the end of the current instruction. I am afraid
this may break somewhere. 
I don't think I can commit this. I was trying to find a proper fix, but I
couldn't come up with any :(. 

[rmcilroy, 2016/03/05 03:01:24]

I'm not sure this is a problem, did you find anything which it fails due to? The
source position for the current bytecode should always end after the last byte
of that bytecode (i.e., on the first byte of the next bytecode), so even
although this is not necessarily on a bytecode boundary, it should still always
fall in the valid range for the correct source position AFAIK. Yang, what do you
think?

         abstract_code = AbstractCode::cast(shared_info->bytecode_array());
       }
       FrameSummary summary(receiver, function, abstract_code, code_offset,