fixed impeller golden content scale (flutter#167308)

fixes flutter#162036

This fixes the problem my scaling the render texture by the content
scalar. This means locally you'll probably be generating 2048x1536
images. This matches the rendering that is happening in playgrounds. On
CI the content scalar should be one so there is no change there.

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Author: gaaclarke

engine/src/flutter/impeller/golden_tests/golden_playground_test_mac.cc

@@ -222,10 +222,16 @@ bool GoldenPlaygroundTest::OpenPlaygroundHere(
   AiksContext renderer(GetContext(), typographer_context_);
 
   std::unique_ptr<testing::Screenshot> screenshot;
+  Point content_scale =
+      pimpl_->screenshotter->GetPlayground().GetContentScale();
+
+  ISize physical_window_size(
+      std::round(pimpl_->window_size.width * content_scale.x),
+      std::round(pimpl_->window_size.height * content_scale.y));
   for (int i = 0; i < 2; ++i) {
     auto display_list = callback();
     auto texture =
-        DisplayListToTexture(display_list, pimpl_->window_size, renderer);
+        DisplayListToTexture(display_list, physical_window_size, renderer);
     screenshot = pimpl_->screenshotter->MakeScreenshot(renderer, texture);
   }
   return SaveScreenshot(std::move(screenshot));
@@ -320,9 +326,14 @@ fml::Status GoldenPlaygroundTest::SetCapabilities(
 std::unique_ptr<testing::Screenshot> GoldenPlaygroundTest::MakeScreenshot(
     const sk_sp<flutter::DisplayList>& list) {
   AiksContext renderer(GetContext(), typographer_context_);
+  Point content_scale =
+      pimpl_->screenshotter->GetPlayground().GetContentScale();
 
+  ISize physical_window_size(
+      std::round(pimpl_->window_size.width * content_scale.x),
+      std::round(pimpl_->window_size.height * content_scale.y));
   return pimpl_->screenshotter->MakeScreenshot(
-      renderer, DisplayListToTexture(list, pimpl_->window_size, renderer));
+      renderer, DisplayListToTexture(list, physical_window_size, renderer));
 }
 
 }  // namespace impeller

engine/src/flutter/impeller/golden_tests/metal_screenshotter.mm

@@ -43,7 +43,7 @@
         imageByApplyingOrientation:kCGImagePropertyOrientationDownMirrored];
 
     CGImageRef cgImage = [cicontext createCGImage:flipped
-                                         fromRect:[ciImage extent]];
+                                         fromRect:[flipped extent]];
 
     // NOLINTNEXTLINE(clang-analyzer-cplusplus.NewDeleteLeaks)
     return std::unique_ptr<MetalScreenshot>(new MetalScreenshot(cgImage));