Issue 23573. Catch exception during indexing.

Issue 23573. Catch exception during indexing.

R=paulberry@google.com
BUG=https://code.google.com/p/dart/issues/detail?id=23573

Committed: https://github.com/dart-lang/sdk/commit/8e439849b3d6f348eda7bf98b65303a5c41bb061

[Paul Berry, 2015-06-02 15:44:40]

https://codereview.chromium.org/1168473003/diff/1/pkg/analysis_server/lib/src...
File pkg/analysis_server/lib/src/operation/operation_analysis.dart (right):

https://codereview.chromium.org/1168473003/diff/1/pkg/analysis_server/lib/src...
pkg/analysis_server/lib/src/operation/operation_analysis.dart:333:
server.sendServerErrorNotification(exception, stackTrace);
Do we know that the index is in a coherent state at this point?  I would have
expected that we would have to take some additional actions in order for it to
be safe for analysis server to resume execution.  (For example, maybe we would
need to clear out any index entries associated with the current unit).

[scheglov, 2015-06-02 16:33:37]

On 2015/06/02 15:44:40, Paul Berry wrote:
>
https://codereview.chromium.org/1168473003/diff/1/pkg/analysis_server/lib/src...
> File pkg/analysis_server/lib/src/operation/operation_analysis.dart (right):
> 
>
https://codereview.chromium.org/1168473003/diff/1/pkg/analysis_server/lib/src...
> pkg/analysis_server/lib/src/operation/operation_analysis.dart:333:
> server.sendServerErrorNotification(exception, stackTrace);
> Do we know that the index is in a coherent state at this point?  I would have
> expected that we would have to take some additional actions in order for it to
> be safe for analysis server to resume execution.  (For example, maybe we would
> need to clear out any index entries associated with the current unit).

The most information that is recorded is not saved to disk until doneIndex()
invocation.
So, it should be pretty safe to just abandon indexing of the unit.

I've added a method to clear information about top-level elements.

[Paul Berry, 2015-06-02 16:38:18]

lgtm, thanks!

[scheglov, 2015-06-02 16:40:26]

Committed patchset #2 (id:20001) manually as
8e439849b3d6f348eda7bf98b65303a5c41bb061 (presubmit successful).