aw: Add allow wait for form database

android_webview/browser/aw_form_database_service.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "android_webview/browser/aw_form_database_service.h"
 
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/synchronization/waitable_event.h"
+#include "base/threading/thread_restrictions.h"
 #include "components/autofill/core/browser/webdata/autofill_table.h"
 #include "components/webdata/common/webdata_constants.h"
 #include "content/public/browser/browser_thread.h"
 
 using base::WaitableEvent;
 using content::BrowserThread;
 
 namespace {
 
 // Callback to handle database error. It seems chrome uses this to
@@ skipping 61 matching lines @@
   WaitableEvent completion(base::WaitableEvent::ResetPolicy::AUTOMATIC,
                            base::WaitableEvent::InitialState::NOT_SIGNALED);
   bool result = false;
   BrowserThread::PostTask(
       BrowserThread::DB,
       FROM_HERE,
       base::Bind(&AwFormDatabaseService::HasFormDataImpl,
                  base::Unretained(this),
                  &completion,
                  &result));
-  completion.Wait();
+  {
+    base::ThreadRestrictions::ScopedAllowWait wait;
+    completion.Wait();
+  }
   return result;
 }
 
 void AwFormDatabaseService::HasFormDataImpl(
     WaitableEvent* completion,
     bool* result) {
   WebDataServiceBase::Handle pending_query_handle =
       autofill_data_->GetCountOfValuesContainedBetween(
           base::Time(), base::Time::Max(), this);
   PendingQuery query;
@@ skipping 17 matching lines @@
   if (it == result_map_.end()) {
     LOG(WARNING) << "Received unexpected callback from web data service";
     return;
   }
   *(it->second.result) = has_form_data;
   it->second.completion->Signal();
   result_map_.erase(h);
 }
 
 }  // namespace android_webview