FIX: Destroy `OptimizedImage` record even if `Upload` record is invalid.

app/models/optimized_image.rb

@@ -130,7 +130,7 @@ class OptimizedImage < ActiveRecord::Base
 
   def destroy
     OptimizedImage.transaction do
-      Discourse.store.remove_optimized_image(self)
+      Discourse.store.remove_optimized_image(self) if self.upload
       super
     end
   end

spec/models/optimized_image_spec.rb

@@ -330,6 +330,18 @@ describe OptimizedImage do
 
   end
 
+  describe '#destroy' do
+    describe 'when upload_id is no longer valid' do
+      it 'should still destroy the record' do
+        image = Fabricate(:optimized_image)
+        image.upload.delete
+        image.reload.destroy
+
+        expect(OptimizedImage.exists?(id: image.id)).to eq(false)
+      end
+    end
+  end
+
 end
 
 class FakeInternalStore