Ensure we use the base CompositorContext's AcquireFrame method when screenshotting

shell/common/rasterizer.cc

@@ -399,9 +399,9 @@ static sk_sp<SkData> ScreenshotLayerTreeAsImage(
   SkMatrix root_surface_transformation;
   root_surface_transformation.reset();
 
-  auto frame = compositor_context.AcquireFrame(surface_context, canvas, nullptr,
-                                               root_surface_transformation,
-                                               false, nullptr);
+  auto frame = compositor_context.flutter::CompositorContext::AcquireFrame(
+      surface_context, canvas, nullptr, root_surface_transformation, false,
+      nullptr);
   canvas->clear(SK_ColorTRANSPARENT);
   frame->Raster(*tree, true);
   canvas->flush();

shell/common/shell_unittests.cc

@@ -10,6 +10,7 @@
 #include <memory>
 
 #include "flutter/flow/layers/layer_tree.h"
+#include "flutter/flow/layers/picture_layer.h"
 #include "flutter/flow/layers/transform_layer.h"
 #include "flutter/fml/command_line.h"
 #include "flutter/fml/make_copyable.h"
@@ -952,5 +953,69 @@ TEST_F(ShellTest, IsolateCanAccessPersistentIsolateData) {
   DestroyShell(std::move(shell), std::move(task_runners));
 }
 
+TEST_F(ShellTest, Screenshot) {
+  auto settings = CreateSettingsForFixture();
+  std::unique_ptr<Shell> shell = CreateShell(settings);
+
+  // Create the surface needed by rasterizer
+  PlatformViewNotifyCreated(shell.get());
+
+  auto configuration = RunConfiguration::InferFromSettings(settings);
+  configuration.SetEntrypoint("emptyMain");
+
+  RunEngine(shell.get(), std::move(configuration));
+
+  LayerTreeBuilder builder = [&](std::shared_ptr<ContainerLayer> root) {
+    SkPictureRecorder recorder;
+    SkCanvas* recording_canvas =
+        recorder.beginRecording(SkRect::MakeXYWH(0, 0, 80, 80));
+    recording_canvas->drawRect(SkRect::MakeXYWH(0, 0, 80, 80),
+                               SkPaint(SkColor4f::FromColor(SK_ColorRED)));
+    auto sk_picture = recorder.finishRecordingAsPicture();
+    fml::RefPtr<SkiaUnrefQueue> queue = fml::MakeRefCounted<SkiaUnrefQueue>(
+        this->GetCurrentTaskRunner(), fml::TimeDelta::FromSeconds(0));
+    auto picture_layer = std::make_shared<PictureLayer>(
+        SkPoint::Make(10, 10),
+        flutter::SkiaGPUObject<SkPicture>({sk_picture, queue}), false, false);
+    root->Add(picture_layer);
+  };
+
+  PumpOneFrame(shell.get(), 100, 100, builder);
+
+  fml::Status result =
+      shell->WaitForFirstFrame(fml::TimeDelta::FromMilliseconds(1000));
+  ASSERT_TRUE(result.ok());
+
+  std::shared_ptr<fml::AutoResetWaitableEvent> latch =
+      std::make_shared<fml::AutoResetWaitableEvent>();
+
+  Rasterizer::Screenshot screenshot;
+  fml::TaskRunner::RunNowOrPostTask(
+      shell->GetTaskRunners().GetGPUTaskRunner(), [&]() {
+        auto rasterizer = shell->GetRasterizer();
+        screenshot = rasterizer->ScreenshotLastLayerTree(
+            Rasterizer::ScreenshotType::CompressedImage, true);
+        latch->Signal();
+      });
+  latch->Wait();
+
+  const char* reference_png =
+      "iVBORw0KGgoAAAANSUhEUgAAAGQAAABkCAYAAABw4pVUAAAAAXNSR0IArs4c6QAAAARzQklU"
+      "CAgICHwIZIgAAADpSURBVHic7dHBCcAwDARBOf337FQQSB6GJcy89Ti0MwAAAEDHenu4Z/"
+      "bJIX+"
+      "3Xv76Oj2EbwSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgS"
+      "JESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgS"
+      "JESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgSJESRGkBhBYgS"
+      "JESRGkBhBYgSJESRGkBhBYgSJEQQAAADg0Q0wHwKgbFGDCQAAAABJRU5ErkJggg==";
+  // Use MakeWithoutCopy instead of MakeWithCString because we don't want to
+  // encode the null sentinel
+  sk_sp<SkData> reference_data =
+      SkData::MakeWithoutCopy(reference_png, strlen(reference_png));
+
+  ASSERT_TRUE(reference_data->equals(screenshot.data.get()));
+
+  DestroyShell(std::move(shell));
+}
+
 }  // namespace testing
 }  // namespace flutter