Make copy of the drivers list in SearchEngineImpl2 to avoid ConcurrentModificationError.

Make copy of the drivers list in SearchEngineImpl2 to avoid ConcurrentModificationError.

I think this happens when a driver is disposed why search is in
progress. So, we need to make defensive copies.

This also makes me realize that we don't handle situations when
a driver instance is disposed, but it has pending requests, such as
getResult(), getIndex(), etc - actually any getXXX(), and search. As
it is now, I think we just leave these Future(s) and they never
complete.

R=brianwilkerson@google.com
BUG=

Committed: https://github.com/dart-lang/sdk/commit/124f874b4aaa0fdb7d6eeda52847bf30e9169e93

[Brian Wilkerson, 2017-04-17 16:35:01]

lgtm

[scheglov, 2017-04-17 16:41:59]

Description was changed from

==========
Make copy of the drivers list in SearchEngineImpl2 to avoid
ConcurrentModificationError.

I think this happens when a driver is disposed why search is in
progress. So, we need to make defensive copies.

This also makes me realize that we don't handle situations when
a driver instance is disposed, but it has pending requests, such as
getResult(), getIndex(), etc - actually any getXXX(), and search. As
it is now, I think we just leave these Future(s) and they never
complete.

R=brianwilkerson@google.com
BUG=
==========

to

==========
Make copy of the drivers list in SearchEngineImpl2 to avoid
ConcurrentModificationError.

I think this happens when a driver is disposed why search is in
progress. So, we need to make defensive copies.

This also makes me realize that we don't handle situations when
a driver instance is disposed, but it has pending requests, such as
getResult(), getIndex(), etc - actually any getXXX(), and search. As
it is now, I think we just leave these Future(s) and they never
complete.

R=brianwilkerson@google.com
BUG=

Committed:
https://github.com/dart-lang/sdk/commit/124f874b4aaa0fdb7d6eeda52847bf30e9169e93
==========

[scheglov, 2017-04-17 16:42:00]

Committed patchset #1 (id:1) manually as
124f874b4aaa0fdb7d6eeda52847bf30e9169e93 (presubmit successful).