Reland "[Windows] Introduce egl::Surface and egl::WindowSurface" (#50148)

# Original pull request description

This introduces the `egl::Surface` and `egl::WindowSurface` types to abstract a raw `EGLSurface`. This also removes some - but not all - EGL surface logic out from `EGLManager`.

Subsequent pull requests will be necessary to:

1. Move ownership of the `egl::WindowSurface` from `egl::Manager` to `FlutterWindowsView`
2. Refactor external texture's off-screen EGL surface to use `egl::Surface`

Part of flutter/flutter#141996

# Reland

#49983 was reverted as it introduced a crash if the render surface fails to be created even though EGL was initialized successfully.

This pull request is split into the following commits:

1. c0b11be is the original pull request unchanged
2. 1dc7813 is the fix: it checks a surface is valid before using it. This also adds several tests to prevent this kind of regression.

[C++, Objective-C, Java style guides]: https://github.com/flutter/engine/blob/main/CONTRIBUTING.md#style

Author: loic-sharma

ci/licenses_golden/licenses_flutter

@@ -7252,6 +7252,10 @@ ORIGIN: ../../../flutter/shell/platform/windows/egl/manager.cc + ../../../flutte
 ORIGIN: ../../../flutter/shell/platform/windows/egl/manager.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/windows/egl/proc_table.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/windows/egl/proc_table.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/windows/egl/surface.cc + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/windows/egl/surface.h + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/windows/egl/window_surface.cc + ../../../flutter/LICENSE
+ORIGIN: ../../../flutter/shell/platform/windows/egl/window_surface.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/windows/event_watcher.cc + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/windows/event_watcher.h + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/shell/platform/windows/external_texture.h + ../../../flutter/LICENSE
@@ -10137,6 +10141,10 @@ FILE: ../../../flutter/shell/platform/windows/egl/manager.cc
 FILE: ../../../flutter/shell/platform/windows/egl/manager.h
 FILE: ../../../flutter/shell/platform/windows/egl/proc_table.cc
 FILE: ../../../flutter/shell/platform/windows/egl/proc_table.h
+FILE: ../../../flutter/shell/platform/windows/egl/surface.cc
+FILE: ../../../flutter/shell/platform/windows/egl/surface.h
+FILE: ../../../flutter/shell/platform/windows/egl/window_surface.cc
+FILE: ../../../flutter/shell/platform/windows/egl/window_surface.h
 FILE: ../../../flutter/shell/platform/windows/event_watcher.cc
 FILE: ../../../flutter/shell/platform/windows/event_watcher.h
 FILE: ../../../flutter/shell/platform/windows/external_texture.h

shell/platform/windows/BUILD.gn

@@ -59,6 +59,10 @@ source_set("flutter_windows_source") {
     "egl/manager.h",
     "egl/proc_table.cc",
     "egl/proc_table.h",
+    "egl/surface.cc",
+    "egl/surface.h",
+    "egl/window_surface.cc",
+    "egl/window_surface.h",
     "event_watcher.cc",
     "event_watcher.h",
     "external_texture.h",
@@ -209,6 +213,7 @@ executable("flutter_windows_unittests") {
     "testing/egl/mock_context.h",
     "testing/egl/mock_manager.h",
     "testing/egl/mock_proc_table.h",
+    "testing/egl/mock_window_surface.h",
     "testing/engine_modifier.h",
     "testing/flutter_window_test.cc",
     "testing/flutter_window_test.h",

shell/platform/windows/compositor_opengl.cc

@@ -97,6 +97,11 @@ bool CompositorOpenGL::Present(const FlutterLayer** layers,
     return false;
   }
 
+  if (!engine_->egl_manager()->surface() ||
+      !engine_->egl_manager()->surface()->IsValid()) {
+    return false;
+  }
+
   // Clear the view if there are no layers to present.
   if (layers_count == 0) {
     // Normally the compositor is initialized when the first backing store is
@@ -128,7 +133,7 @@ bool CompositorOpenGL::Present(const FlutterLayer** layers,
     return false;
   }
 
-  if (!engine_->egl_manager()->MakeCurrent()) {
+  if (!engine_->egl_manager()->surface()->MakeCurrent()) {
     return false;
   }
 
@@ -154,7 +159,7 @@ bool CompositorOpenGL::Present(const FlutterLayer** layers,
                        GL_NEAREST            // filter
   );
 
-  if (!engine_->egl_manager()->SwapBuffers()) {
+  if (!engine_->egl_manager()->surface()->SwapBuffers()) {
     return false;
   }
 
@@ -165,7 +170,17 @@ bool CompositorOpenGL::Present(const FlutterLayer** layers,
 bool CompositorOpenGL::Initialize() {
   FML_DCHECK(!is_initialized_);
 
-  if (!engine_->egl_manager()->MakeCurrent()) {
+  egl::Manager* manager = engine_->egl_manager();
+  if (!manager) {
+    return false;
+  }
+
+  egl::Surface* surface = manager->surface();
+  if (!surface || !surface->IsValid()) {
+    return false;
+  }
+
+  if (!surface->MakeCurrent()) {
     return false;
   }
 
@@ -186,14 +201,14 @@ bool CompositorOpenGL::ClearSurface() {
   // Resize the surface if needed.
   engine_->view()->OnEmptyFrameGenerated();
 
-  if (!engine_->egl_manager()->MakeCurrent()) {
+  if (!engine_->egl_manager()->surface()->MakeCurrent()) {
     return false;
   }
 
   gl_->ClearColor(0.0f, 0.0f, 0.0f, 0.0f);
   gl_->Clear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
 
-  if (!engine_->egl_manager()->SwapBuffers()) {
+  if (!engine_->egl_manager()->surface()->SwapBuffers()) {
     return false;
   }
 

shell/platform/windows/compositor_opengl_unittests.cc

@@ -10,6 +10,7 @@
 #include "flutter/shell/platform/windows/egl/manager.h"
 #include "flutter/shell/platform/windows/flutter_windows_view.h"
 #include "flutter/shell/platform/windows/testing/egl/mock_manager.h"
+#include "flutter/shell/platform/windows/testing/egl/mock_window_surface.h"
 #include "flutter/shell/platform/windows/testing/engine_modifier.h"
 #include "flutter/shell/platform/windows/testing/flutter_windows_engine_builder.h"
 #include "flutter/shell/platform/windows/testing/mock_window_binding_handler.h"
@@ -65,20 +66,29 @@ class CompositorOpenGLTest : public WindowsTest {
  protected:
   FlutterWindowsEngine* engine() { return engine_.get(); }
   egl::MockManager* egl_manager() { return egl_manager_; }
+  egl::MockWindowSurface* surface() { return surface_.get(); }
 
-  void UseHeadlessEngine() {
+  void UseHeadlessEngine(bool add_surface = true) {
     auto egl_manager = std::make_unique<egl::MockManager>();
     egl_manager_ = egl_manager.get();
 
+    if (add_surface) {
+      surface_ = std::make_unique<egl::MockWindowSurface>();
+      EXPECT_CALL(*egl_manager_, surface)
+          .WillRepeatedly(Return(surface_.get()));
+    } else {
+      EXPECT_CALL(*egl_manager_, surface).WillRepeatedly(Return(nullptr));
+    }
+
     FlutterWindowsEngineBuilder builder{GetContext()};
 
     engine_ = builder.Build();
     EngineModifier modifier(engine_.get());
     modifier.SetEGLManager(std::move(egl_manager));
   }
 
-  void UseEngineWithView() {
-    UseHeadlessEngine();
+  void UseEngineWithView(bool add_surface = true) {
+    UseHeadlessEngine(add_surface);
 
     auto window = std::make_unique<MockWindowBindingHandler>();
     EXPECT_CALL(*window.get(), SetView).Times(1);
@@ -92,6 +102,7 @@ class CompositorOpenGLTest : public WindowsTest {
  private:
   std::unique_ptr<FlutterWindowsEngine> engine_;
   std::unique_ptr<FlutterWindowsView> view_;
+  std::unique_ptr<egl::MockWindowSurface> surface_;
   egl::MockManager* egl_manager_;
 
   FML_DISALLOW_COPY_AND_ASSIGN(CompositorOpenGLTest);
@@ -107,7 +118,8 @@ TEST_F(CompositorOpenGLTest, CreateBackingStore) {
   FlutterBackingStoreConfig config = {};
   FlutterBackingStore backing_store = {};
 
-  EXPECT_CALL(*egl_manager(), MakeCurrent).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), IsValid).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), MakeCurrent).WillOnce(Return(true));
   ASSERT_TRUE(compositor.CreateBackingStore(config, &backing_store));
   ASSERT_TRUE(compositor.CollectBackingStore(&backing_store));
 }
@@ -120,7 +132,8 @@ TEST_F(CompositorOpenGLTest, InitializationFailure) {
   FlutterBackingStoreConfig config = {};
   FlutterBackingStore backing_store = {};
 
-  EXPECT_CALL(*egl_manager(), MakeCurrent).WillOnce(Return(false));
+  EXPECT_CALL(*surface(), IsValid).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), MakeCurrent).WillOnce(Return(false));
   EXPECT_FALSE(compositor.CreateBackingStore(config, &backing_store));
 }
 
@@ -132,16 +145,17 @@ TEST_F(CompositorOpenGLTest, Present) {
   FlutterBackingStoreConfig config = {};
   FlutterBackingStore backing_store = {};
 
-  EXPECT_CALL(*egl_manager(), MakeCurrent).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), IsValid).WillRepeatedly(Return(true));
+  EXPECT_CALL(*surface(), MakeCurrent).WillOnce(Return(true));
   ASSERT_TRUE(compositor.CreateBackingStore(config, &backing_store));
 
   FlutterLayer layer = {};
   layer.type = kFlutterLayerContentTypeBackingStore;
   layer.backing_store = &backing_store;
   const FlutterLayer* layer_ptr = &layer;
 
-  EXPECT_CALL(*egl_manager(), MakeCurrent).WillOnce(Return(true));
-  EXPECT_CALL(*egl_manager(), SwapBuffers).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), MakeCurrent).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), SwapBuffers).WillOnce(Return(true));
   EXPECT_TRUE(compositor.Present(&layer_ptr, 1));
 
   ASSERT_TRUE(compositor.CollectBackingStore(&backing_store));
@@ -154,10 +168,9 @@ TEST_F(CompositorOpenGLTest, PresentEmpty) {
 
   // The context will be bound twice: first to initialize the compositor, second
   // to clear the surface.
-  EXPECT_CALL(*egl_manager(), MakeCurrent)
-      .Times(2)
-      .WillRepeatedly(Return(true));
-  EXPECT_CALL(*egl_manager(), SwapBuffers).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), IsValid).WillRepeatedly(Return(true));
+  EXPECT_CALL(*surface(), MakeCurrent).Times(2).WillRepeatedly(Return(true));
+  EXPECT_CALL(*surface(), SwapBuffers).WillOnce(Return(true));
   EXPECT_TRUE(compositor.Present(nullptr, 0));
 }
 
@@ -169,7 +182,8 @@ TEST_F(CompositorOpenGLTest, HeadlessPresentIgnored) {
   FlutterBackingStoreConfig config = {};
   FlutterBackingStore backing_store = {};
 
-  EXPECT_CALL(*egl_manager(), MakeCurrent).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), IsValid).WillOnce(Return(true));
+  EXPECT_CALL(*surface(), MakeCurrent).WillOnce(Return(true));
   ASSERT_TRUE(compositor.CreateBackingStore(config, &backing_store));
 
   FlutterLayer layer = {};
@@ -182,5 +196,23 @@ TEST_F(CompositorOpenGLTest, HeadlessPresentIgnored) {
   ASSERT_TRUE(compositor.CollectBackingStore(&backing_store));
 }
 
+TEST_F(CompositorOpenGLTest, NoSurfaceIgnored) {
+  UseEngineWithView(/*add_surface = */ false);
+
+  auto compositor = CompositorOpenGL{engine(), kMockResolver};
+
+  FlutterBackingStoreConfig config = {};
+  FlutterBackingStore backing_store = {};
+
+  ASSERT_FALSE(compositor.CreateBackingStore(config, &backing_store));
+
+  FlutterLayer layer = {};
+  layer.type = kFlutterLayerContentTypeBackingStore;
+  layer.backing_store = nullptr;
+  const FlutterLayer* layer_ptr = &layer;
+
+  EXPECT_FALSE(compositor.Present(&layer_ptr, 1));
+}
+
 }  // namespace testing
 }  // namespace flutter

shell/platform/windows/egl/context.h

@@ -14,7 +14,7 @@ namespace egl {
 
 // An EGL context to interact with OpenGL.
 //
-// This enables automatic eror logging and mocking.
+// This enables automatic error logging and mocking.
 //
 // Flutter Windows uses this to create render and resource contexts.
 class Context {