[Impeller] finish experimental canvas changes. (#54569)

Make sure the old dispatcher cannot be used if the new dispatcher is enabled. Migrate tests using old canvas to new canvas, mostly to make deleting the old one easier...

Author: jonahwilliams

display_list/testing/dl_test_surface_metal.cc

@@ -87,6 +87,11 @@ sk_sp<DlPixelData> DlMetalSurfaceProvider::ImpellerSnapshot(
     const sk_sp<DisplayList>& list,
     int width,
     int height) const {
+#if EXPERIMENTAL_CANVAS
+  auto texture = DisplayListToTexture(list, {width, height}, *aiks_context_);
+  return sk_make_sp<DlMetalPixelData>(
+      snapshotter_->MakeScreenshot(*aiks_context_, texture));
+#else
   InitScreenShotter();
   impeller::DlDispatcher dispatcher;
   dispatcher.drawColor(flutter::DlColor::kTransparent(),
@@ -95,13 +100,19 @@ sk_sp<DlPixelData> DlMetalSurfaceProvider::ImpellerSnapshot(
   auto picture = dispatcher.EndRecordingAsPicture();
   return sk_make_sp<DlMetalPixelData>(snapshotter_->MakeScreenshot(
       *aiks_context_, picture, {width, height}, false));
+
+#endif  // EXPERIMENTAL_CANVAS
 }
 
 sk_sp<DlImage> DlMetalSurfaceProvider::MakeImpellerImage(
     const sk_sp<DisplayList>& list,
     int width,
     int height) const {
   InitScreenShotter();
+#if EXPERIMENTAL_CANVAS
+  return impeller::DlImageImpeller::Make(
+      DisplayListToTexture(list, {width, height}, *aiks_context_));
+#else
   impeller::DlDispatcher dispatcher;
   dispatcher.drawColor(flutter::DlColor::kTransparent(),
                        flutter::DlBlendMode::kSrc);
@@ -111,6 +122,8 @@ sk_sp<DlImage> DlMetalSurfaceProvider::MakeImpellerImage(
       picture.ToImage(*aiks_context_, {width, height});
   std::shared_ptr<impeller::Texture> texture = image->GetTexture();
   return impeller::DlImageImpeller::Make(texture);
+
+#endif  // EXPERIMENTAL_CANVAS
 }
 
 void DlMetalSurfaceProvider::InitScreenShotter() const {