ozone/platform/wayland: Use more realistic event processing and request flushing in tests

ui/ozone/platform/wayland/fake_server.cc

 // Copyright 2016 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 "ui/ozone/platform/wayland/fake_server.h"
 
 #include <sys/socket.h>
 #include <wayland-server.h>
 #include <xdg-shell-unstable-v5-server-protocol.h>
 
 #include "base/bind.h"
 #include "base/files/scoped_file.h"
+#include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
 
 namespace wl {
 namespace {
 
 const uint32_t kCompositorVersion = 4;
 const uint32_t kXdgShellVersion = 1;
 
 void DestroyResource(wl_client* client, wl_resource* resource) {
   wl_resource_destroy(resource);
@@ skipping 244 matching lines @@
 void DisplayDeleter::operator()(wl_display* display) {
   wl_display_destroy(display);
 }
 
 FakeServer::FakeServer()
     : Thread("fake_wayland_server"),
       pause_event_(false, false),
       resume_event_(false, false) {}
 
 FakeServer::~FakeServer() {
+  Resume();
   Stop();
 }
 
 bool FakeServer::Start() {
   display_.reset(wl_display_create());
   if (!display_)
     return false;
   event_loop_ = wl_display_get_event_loop(display_.get());
 
   int fd[2];
@@ skipping 18 matching lines @@
   options.message_pump_factory =
       base::Bind(&FakeServer::CreateMessagePump, base::Unretained(this));
   if (!base::Thread::StartWithOptions(options))
     return false;
 
   setenv("WAYLAND_SOCKET", base::UintToString(client_fd.release()).c_str(), 1);
 
   return true;
 }
 
-void FakeServer::Flush() {
-  wl_display_flush_clients(display_.get());
-}
-
 void FakeServer::Pause() {
   task_runner()->PostTask(
       FROM_HERE, base::Bind(&FakeServer::DoPause, base::Unretained(this)));
   pause_event_.Wait();
 }
 
 void FakeServer::Resume() {
+  if (display_)
+    wl_display_flush_clients(display_.get());
   resume_event_.Signal();
 }
 
 void FakeServer::DoPause() {
+  base::RunLoop().RunUntilIdle();
   pause_event_.Signal();
   resume_event_.Wait();
 }
 
 scoped_ptr<base::MessagePump> FakeServer::CreateMessagePump() {
   auto pump = make_scoped_ptr(new base::MessagePumpLibevent);
   pump->WatchFileDescriptor(wl_event_loop_get_fd(event_loop_), true,
                             base::MessagePumpLibevent::WATCH_READ, &controller_,
                             this);
   return std::move(pump);
 }
 
 void FakeServer::OnFileCanReadWithoutBlocking(int fd) {
   wl_event_loop_dispatch(event_loop_, 0);
   wl_display_flush_clients(display_.get());
 }
 
 void FakeServer::OnFileCanWriteWithoutBlocking(int fd) {}
 
 }  // namespace wl