Processes avatar_images for gr.Chatbot and icon for gr.Button correctly, so that respective files are moved to cache

[abidlabs]

Closes: #6329

Test with chatbot_multimodal demo

[gradio-pr-bot]

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Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/0ffd4d0a1e2e190ad33810af31f3947f7b49dbc1/gradio-4.2.0-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@0ffd4d0a1e2e190ad33810af31f3947f7b49dbc1#subdirectory=client/python"

[gradio-pr-bot]

🦄 change detected

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Processes avatar_images for gr.Chatbot and icon for gr.Button correctly, so that respective files are moved to cache

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[aliabid94]

LGTM. Seems like it would be cleaner to move move_resource_to_block_cache to be a Block method, instead of having to pass self everywhere it's called.

[abidlabs]

Thanks @aliabid94. That's a good idea, I'll make the change

[abidlabs]

I'll refactor it so that the Block class has its own move_resource_to_block_cache() instance method, but I'll also leave the original move_resource_to_block_cache method in postprocessing_utils.py for backwards compatibility for any custom components created in Gradio 4.2.0 or earlier.

[aliabid94]

I'll also leave the original move_resource_to_block_cache method in postprocessing_utils.py for backwards compatibility

Then have postprocessing_utils.move_resource_to_block_cache just call the block.move_resource_to_block_cache?

[abidlabs]

Made the refactor, and then also included a test using the gradio_pdf custom component that @freddyaboulton created to ensure backwards compatibility. Will merge after CI is green. Thanks for the review @aliabid94!