Fix threading issues in WebDataRequestManager.

components/webdata/common/web_database_backend.cc

Index: components/webdata/common/web_database_backend.cc
diff --git a/components/webdata/common/web_database_backend.cc b/components/webdata/common/web_database_backend.cc
index a4446061f91307de7084ab03a4376ef5f0adfad7..7dbf642b029d522e01527616df63c55cc5b848fb 100644
--- a/components/webdata/common/web_database_backend.cc
+++ b/components/webdata/common/web_database_backend.cc
@@ -52,11 +52,11 @@ void WebDatabaseBackend::ShutdownDatabase() {
 void WebDatabaseBackend::DBWriteTaskWrapper(
     const WebDatabaseService::WriteTask& task,
     std::unique_ptr<WebDataRequest> request) {
-  if (request->IsCancelled())
+  if (!request->IsActive())
     return;
 
   ExecuteWriteTask(task);
-  request_manager_->RequestCompleted(std::move(request));
+  request_manager_->RequestCompleted(std::move(request), nullptr);
 }
 
 void WebDatabaseBackend::ExecuteWriteTask(
@@ -72,11 +72,11 @@ void WebDatabaseBackend::ExecuteWriteTask(
 void WebDatabaseBackend::DBReadTaskWrapper(
     const WebDatabaseService::ReadTask& task,
     std::unique_ptr<WebDataRequest> request) {
-  if (request->IsCancelled())
+  if (!request->IsActive())
     return;
 
-  request->SetResult(ExecuteReadTask(task));
-  request_manager_->RequestCompleted(std::move(request));
+  std::unique_ptr<WDTypedResult> result = ExecuteReadTask(task);
+  request_manager_->RequestCompleted(std::move(request), std::move(result));
 }
 
 std::unique_ptr<WDTypedResult> WebDatabaseBackend::ExecuteReadTask(