Fix data race in IndexedDBDatabaseCallbacksImpl::Abort

Fix data race in IndexedDBDatabaseCallbacksImpl::Abort

It is not safe to pass a WebIDBDatabaseError between threads because it
contains non-threadsafe WebStrings. This change passes the components
necessary to construct the error object across threads and creates it
there.

BUG=665055
Committed: https://crrev.com/3aa3a7b9ad75d9475df4340b5ed86c3d6240f3fa
Cr-Commit-Position: refs/heads/master@{#432019}

[Reilly Grant (use Gerrit), 2016-11-14 23:14:00]

The CQ bit was checked by reillyg@chromium.org to run a CQ dry run

[Reilly Grant (use Gerrit), 2016-11-14 23:14:31]

reillyg@chromium.org changed reviewers:
+ jsbell@chromium.org

[Reilly Grant (use Gerrit), 2016-11-14 23:14:32]

Please take a look.

[commit-bot: I haz the power, 2016-11-14 23:15:52]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[jsbell, 2016-11-14 23:25:08]

lgtm

dmurph@ - FYI, will likely collide with changes you have in progress (but
probably in a good way)

[Reilly Grant (use Gerrit), 2016-11-14 23:26:41]

The CQ bit was unchecked by reillyg@chromium.org

[Reilly Grant (use Gerrit), 2016-11-14 23:26:44]

The CQ bit was checked by reillyg@chromium.org

[commit-bot: I haz the power, 2016-11-14 23:27:23]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-15 00:35:27]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-11-15 00:35:28]

Failed to apply patch for
content/child/indexed_db/indexed_db_database_callbacks_impl.cc:
While running git apply --index -p1;
  error: patch failed:
content/child/indexed_db/indexed_db_database_callbacks_impl.cc:23
  error: content/child/indexed_db/indexed_db_database_callbacks_impl.cc: patch
does not apply

Patch:       content/child/indexed_db/indexed_db_database_callbacks_impl.cc
Index: content/child/indexed_db/indexed_db_database_callbacks_impl.cc
diff --git a/content/child/indexed_db/indexed_db_database_callbacks_impl.cc
b/content/child/indexed_db/indexed_db_database_callbacks_impl.cc
index
4eab2f93bbfe8855a414fe5a63e71ca2258e5a89..1ae0b2d03d64e80d95b4d7f95755185968298873
100644
--- a/content/child/indexed_db/indexed_db_database_callbacks_impl.cc
+++ b/content/child/indexed_db/indexed_db_database_callbacks_impl.cc
@@ -23,6 +23,13 @@ void DeleteDatabaseCallbacks(WebIDBDatabaseCallbacks*
callbacks,
   delete callbacks;
 }
 
+void BuildErrorAndAbort(WebIDBDatabaseCallbacks* callbacks,
+                        int64_t transaction_id,
+                        int32_t code,
+                        const base::string16& message) {
+  callbacks->onAbort(transaction_id, blink::WebIDBDatabaseError(code,
message));
+}
+
 }  // namespace
 
 IndexedDBDatabaseCallbacksImpl::IndexedDBDatabaseCallbacksImpl(
@@ -59,10 +66,11 @@ void IndexedDBDatabaseCallbacksImpl::VersionChange(int64_t
old_version,
 void IndexedDBDatabaseCallbacksImpl::Abort(int64_t transaction_id,
                                            int32_t code,
                                            const base::string16& message) {
+  // Indirect through BuildErrorAndAbort because it isn't safe to pass a
+  // WebIDBDatabaseError between threads.
   callback_runner_->PostTask(
-      FROM_HERE, base::Bind(&WebIDBDatabaseCallbacks::onAbort,
-                            base::Unretained(callbacks_), transaction_id,
-                            blink::WebIDBDatabaseError(code, message)));
+      FROM_HERE, base::Bind(&BuildErrorAndAbort, base::Unretained(callbacks_),
+                            transaction_id, code, message));
 }
 
 void IndexedDBDatabaseCallbacksImpl::Complete(int64_t transaction_id) {

[commit-bot: I haz the power, 2016-11-15 00:39:52]

Description was changed from

==========
Fix data race in IndexedDBDatabaseCallbacksImpl::Abort

It is not safe to pass a WebIDBDatabaseError between threads because it
contains non-threadsafe WebStrings. This change passes the components
necessary to construct the error object across threads and creates it
there.

BUG=665055
==========

to

==========
Fix data race in IndexedDBDatabaseCallbacksImpl::Abort

It is not safe to pass a WebIDBDatabaseError between threads because it
contains non-threadsafe WebStrings. This change passes the components
necessary to construct the error object across threads and creates it
there.

BUG=665055

Committed: https://crrev.com/3aa3a7b9ad75d9475df4340b5ed86c3d6240f3fa
Cr-Commit-Position: refs/heads/master@{#432019}
==========

[commit-bot: I haz the power, 2016-11-15 00:39:53]

Patchset 1 (id:??) landed as
https://crrev.com/3aa3a7b9ad75d9475df4340b5ed86c3d6240f3fa
Cr-Commit-Position: refs/heads/master@{#432019}