Debugger: fix crash when debugger is enabled between parsing and compiling.

Debugger: fix crash when debugger is enabled between parsing and compiling.

The background parser checks for debugger state in its constructor. This
is not good enough, since the debugger state may change afterwards, but
before compiling takes place. As the background parser can only parse
lazily, this could mean that due to debugging, we try to eagerly compile
an inner function we have not eagerly parsed.

R=jochen@chromium.org

Committed: https://crrev.com/e8752eb9cef68297ff34cf9d87d187d679677f62
Cr-Commit-Position: refs/heads/master@{#29784}

[Yang, 2015-07-21 08:40:40]

Please take a look.

https://codereview.chromium.org/1247743002/diff/1/src/compiler.cc
File src/compiler.cc (left):

https://codereview.chromium.org/1247743002/diff/1/src/compiler.cc#oldcode1337
src/compiler.cc:1337: // real code caching lands, streaming needs to be adapted
to use it.
For the current strategy used in Chrome this is not necessary. We never produce
code cache on first parse/compile anyways. Instead of set a time stamp to
support code caching decision at a later time.

[jochen (gone - plz use gerrit), 2015-07-21 08:45:01]

jochen@chromium.org changed reviewers:
+ vogelheim@chromium.org

[jochen (gone - plz use gerrit), 2015-07-21 08:45:02]

+vogelheim

[vogelheim, 2015-07-21 13:22:09]

lgtm

Nice unit test. :)

One nitpick/suggestion: Maybe add a DCHECK for !(is_debug() &&
allow_lazy_parsing()) .... somewhere.

I guess there's a part somewhere - presumably towards the end of CompileTopLevel
(???) - from where on we assume this invariant  holds, and whichever code path
leads there is responsible for making sure it is so. Using a DCHECK as a gentle
reminder for future contributors might be helpful.

[Yang, 2015-07-22 07:09:56]

Assertion added as suggested.

[Yang, 2015-07-22 07:10:01]

The CQ bit was checked by yangguo@chromium.org

[Yang, 2015-07-22 07:10:01]

The patchset sent to the CQ was uploaded after l-g-t-m from
vogelheim@chromium.org
Link to the patchset: https://codereview.chromium.org/1247743002/#ps20001
(title: "added assertion")

[commit-bot: I haz the power, 2015-07-22 07:10:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1247743002/20001

[commit-bot: I haz the power, 2015-07-22 07:37:27]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-07-22 07:37:47]

Patchset 2 (id:??) landed as
https://crrev.com/e8752eb9cef68297ff34cf9d87d187d679677f62
Cr-Commit-Position: refs/heads/master@{#29784}