ozone/wayland: fix wayland fuzzer.

We don't have a fuzzer bot for ozone running and that's why
we failed to spot when the fuzzer became broken.

However, given that I started to enable use_x11 && use_ozone at
the same time, the linux-libfuzzer-asan-rel started to compile
the wayland fuzzer, and that revealed some compilation problems.

This CL fixes that. The design of initialization of the test env
was taken from other fuzzer tests. For example,
ui/gfx/render_text_fuzzer.cc

Bug: 578890
Change-Id: I1517731dc531cb48934cbdbd35023adea818c7e4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2322706Reviewed-by: Nick Yamane <nickdiego@igalia.com>
Commit-Queue: Maksim Sisov (GMT+3) <msisov@igalia.com>
Cr-Commit-Position: refs/heads/master@{#792208}

ui/ozone/platform/wayland/fuzzer/wayland_buffer_fuzzer.cc

@@ -17,6 +17,8 @@
 #include "base/files/file_util.h"
 #include "base/message_loop/message_pump_type.h"
 #include "base/task/single_thread_task_executor.h"
+#include "base/test/task_environment.h"
+#include "base/test/test_timeouts.h"
 #include "mojo/core/embedder/embedder.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "ui/gfx/geometry/rect.h"
@@ -50,14 +52,27 @@ class MockPlatformWindowDelegate : public ui::PlatformWindowDelegate {
                void(gfx::AcceleratedWidget widget));
   MOCK_METHOD0(OnAcceleratedWidgetDestroyed, void());
   MOCK_METHOD1(OnActivationChanged, void(bool active));
+  MOCK_METHOD0(OnMouseEnter, void());
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MockPlatformWindowDelegate);
 };
 
+struct Environment {
+  Environment()
+      : task_environment((base::CommandLine::Init(0, nullptr),
+                          TestTimeouts::Initialize(),
+                          base::test::TaskEnvironment::MainThreadType::UI)) {
+    logging::SetMinLogLevel(logging::LOG_FATAL);
+  }
+
+  base::test::TaskEnvironment task_environment;
+};
+
 }  // namespace
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  static Environment env;
   FuzzedDataProvider data_provider(data, size);
 
   mojo::core::Init();
@@ -69,8 +84,6 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
       DRM_FORMAT_XRGB2101010, DRM_FORMAT_XBGR2101010, DRM_FORMAT_RGB565,
       DRM_FORMAT_NV12,        DRM_FORMAT_YVU420};
 
-  base::SingleThreadTaskExecutor main_task_executor(base::MessagePumpType::UI);
-
   wl::TestWaylandServerThread server;
   CHECK(server.Start(6));
 
@@ -82,8 +95,6 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
       connection.get());
 
   MockPlatformWindowDelegate delegate;
-  std::unique_ptr<ui::WaylandWindow> window =
-      std::make_unique<ui::WaylandWindow>(&delegate, connection.get());
   gfx::AcceleratedWidget widget = gfx::kNullAcceleratedWidget;
 
   EXPECT_CALL(delegate, OnAcceleratedWidgetAvailable(_))
@@ -91,11 +102,13 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
   ui::PlatformWindowInitProperties properties;
   properties.bounds = gfx::Rect(0, 0, 800, 600);
   properties.type = ui::PlatformWindowType::kWindow;
-  CHECK(window->Initialize(std::move(properties)));
+  std::unique_ptr<ui::WaylandWindow> window = ui::WaylandWindow::Create(
+      &delegate, connection.get(), std::move(properties));
+
   CHECK_NE(widget, gfx::kNullAcceleratedWidget);
 
   // Wait until everything is initialised.
-  base::RunLoop().RunUntilIdle();
+  env.task_environment.RunUntilIdle();
 
   base::FilePath temp_dir, temp_path;
   base::ScopedFD fd =
@@ -131,16 +144,16 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
   EXPECT_CALL(*server.zwp_linux_dmabuf_v1(), CreateParams(_, _, _));
   auto* manager_host = connection->buffer_manager_host();
   manager_host->CreateDmabufBasedBuffer(
-      widget, mojo::PlatformHandle(std::move(fd)), buffer_size, strides,
-      offsets, modifiers, kFormat, kPlaneCount, kBufferId);
+      mojo::PlatformHandle(std::move(fd)), buffer_size, strides, offsets,
+      modifiers, kFormat, kPlaneCount, kBufferId);
 
   // Wait until the buffers are created.
-  base::RunLoop().RunUntilIdle();
+  env.task_environment.RunUntilIdle();
 
   manager_host->DestroyBuffer(widget, kBufferId);
 
   // Wait until the buffers are destroyed.
-  base::RunLoop().RunUntilIdle();
+  env.task_environment.RunUntilIdle();
 
   // Pause the server so it is not running when mock expectations are validated.
   server.Pause();