Add ability for Function to generate source

Add ability for Function to generate source

BUG=
R=hausner@google.com

Committed: https://code.google.com/p/dart/source/detail?r=30239

[hausner, 2013-11-05 22:30:04]

While what you have works, I suggest doing this a bit differently. See below.

https://codereview.chromium.org/60993002/diff/30001/runtime/vm/object.cc
File runtime/vm/object.cc (right):

https://codereview.chromium.org/60993002/diff/30001/runtime/vm/object.cc#newc...
runtime/vm/object.cc:5446: RawString* Function::GenerateSource() {
I suggest making this a bit more smart. If we do have the source code for the
function, we should return the original source code, not synthesized sources.
Maybe add a function to class Script that returns either the actual source code
between two tokens (rounded to beginning and end of line possibly) or generated
source code if there is no source code available.

https://codereview.chromium.org/60993002/diff/30001/runtime/vm/object.cc#newc...
runtime/vm/object.cc:6278: if ((end_tok_pos > 0) && (iterator.CurrentPosition()
> end_tok_pos)) {
Is end_token_pos inclusive or exclusive? Typically we use exclusive end
positions. In that case, the comparison should be >=. In any case, maybe a
comment in the header file would be good to clarify.

[Cutch, 2013-11-05 23:38:25]

PTAL at Patch Set 3.

[hausner, 2013-11-06 23:19:24]

LGTM.

[Cutch, 2013-11-13 18:09:49]

Committed patchset #5 manually as r30239 (presubmit successful).