Switching from AR to Standard view on low memory devices causes the Web3D (Standard veiw) models to not load

[blundellj]

To reproduce:

1. Use a mobile device with low memory (or force the device to use most of it's memory)
2. Load the dev spacesuit scene
3. Start AR mode
4. Return to standard mode
5. Notice the toasts that appear stating "Failed to load model derivative: [object ProgressEvent]"

Some solutions could be

• Because we are switching contexts (AR view to standard view) there is no need to maintain continuity between the two modes. Thus we could just unload the AR model from memory before loading the standard view model (which it seems lit what happens when you enter AR mode currently, unloading the standard view model, then loading the ar model?)
• or when returning to standard view, first load the much smaller 3D thumbnail before loading the standard view model so only a small model is in memory as we load the standard view model

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