egl/x11: Created a child window to control resizes and prevent flashes

ui/gl/gl_surface_egl_x11.h

+// Copyright (c) 2015 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.
+
+#ifndef UI_GL_GL_SURFACE_EGL_X11_H_
+#define UI_GL_GL_SURFACE_EGL_X11_H_
+
+#include <string>
+
+#include "base/macros.h"
+#include "ui/events/platform/platform_event_dispatcher.h"
+#include "ui/gl/gl_surface_egl.h"
+
+namespace gfx {
+
+// Encapsulates an EGL surface bound to a view using the X Window System.
+class GL_EXPORT NativeViewGLSurfaceEGLX11 : public NativeViewGLSurfaceEGL,
+                                            public ui::PlatformEventDispatcher {
+ public:
+  explicit NativeViewGLSurfaceEGLX11(EGLNativeWindowType window);
+
+  // NativeViewGLSurfaceEGL overrides.
+  EGLConfig GetConfig() override;
+  void Destroy() override;
+  bool Resize(const gfx::Size& size, float scale_factor) override;
+  bool InitializeNativeWindow() override;
+
+ private:
+  ~NativeViewGLSurfaceEGLX11() override;
+
+  EGLNativeWindowType parent_window_;
+
+  // PlatformEventDispatcher implementation.
+  bool CanDispatchEvent(const ui::PlatformEvent& event) override;
+  uint32_t DispatchEvent(const ui::PlatformEvent& event) override;
+
+  DISALLOW_COPY_AND_ASSIGN(NativeViewGLSurfaceEGLX11);
+};
+
+}  // namespace gfx
+
+#endif  // UI_GL_GL_SURFACE_EGL_X11_H_