Make error messages about private scripts more descriptive

Make error messages about private scripts more descriptive

Instead of just crashing with RELEASE_ASSERT(), we should print more descriptive
error messages to help debug private scripts.

BUG=341031
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=178046

[haraken, 2014-07-14 05:56:06]

PTAL

[abarth-chromium, 2014-07-14 06:11:41]

LGTM

[abarth-chromium, 2014-07-14 06:12:51]

Consider using FATAL from Assertions.h isntead.

[abarth-chromium, 2014-07-14 06:14:02]

Not sure if FATAL works in release.  There's got to be something better to use
from WTF logging in Assertions.h than fprintf to stderr

[haraken, 2014-07-14 10:21:56]

On 2014/07/14 06:14:02, abarth wrote:
> Not sure if FATAL works in release.  There's got to be something better to use
> from WTF logging in Assertions.h than fprintf to stderr

FATAL is not enabled in release builds but is fine, because it's enough if we
can get the error messages in debug builds.

[haraken, 2014-07-14 10:22:09]

The CQ bit was checked by haraken@chromium.org

[commit-bot: I haz the power, 2014-07-14 10:22:16]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/haraken@chromium.org/389913003/20001

[commit-bot: I haz the power, 2014-07-14 11:32:20]

Change committed as 178046

[arv (Not doing code reviews), 2014-07-14 14:50:57]

LGTM

[Justin Novosad, 2014-07-14 15:51:11]

A revert of this CL has been created in
https://codereview.chromium.org/394493003/ by junov@chromium.org.

The reason for reverting is: Speculative revert for telemetry unit tests failing
on mac.  Failing tests are tests that deliberately execute scripts that crash
the tab. This CL is in the regression range (178046:178054) and seems highly
related.

[Justin Novosad, 2014-07-14 16:08:19]

On 2014/07/14 15:51:11, junov wrote:
> A revert of this CL has been created in
> https://codereview.chromium.org/394493003/ by mailto:junov@chromium.org.
> 
> The reason for reverting is: Speculative revert for telemetry unit tests
failing
> on mac.  Failing tests are tests that deliberately execute scripts that crash
> the tab. This CL is in the regression range (178046:178054) and seems highly
> related.

Revert was aborted.  This CL is not to blame.