EncodeBase64 and DecodeBase64 ops

[vabarbosa]

This is a re-submission of the EncodeBase64/DecodeBase64 PRs that were in tfjs-core / tfjs-converter / tfjs-node and archived as part of the move to monorepo:

• EncodeBase64 and DecodeBase64 ops tfjs-core#1779
• EncodeBase64 and DecodeBase64 ops tfjs-converter#376
• EncodeBase64 and DecodeBase64 ops tfjs-node#259

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the TF implementation of the pix2pix model which fails conversion because of

Unsupported Ops: DecodeJpeg, EncodePng, DecodeBase64

the Open NSFW model also fails conversion with some of the same ops (#433).

i wanted to try to implement some of these ops in TensorFlow.js. starting with this pull request for DecodeBase64 and EncodeBase64.

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[vabarbosa]

hello @nsthorat @pyu10055 this is a re-submission of the EncodeBase64/DecodeBase64 PRs that were originially in tfjs-core / tfjs-converter / tfjs-node repos and since archived as part of the move to monorepo. is there anything else needed from me here?

regarding the build failure, looking at the details/log it shows

ERROR: build step 2 "node:10" failed: exit status 2
ERROR: build step 3 "gcr.io/cloud-builders/gcloud" failed: exit status 1

i am not sure at first glance how they maybe related to the code changes. is this something i should be trying to investigate further myself? thanks again.

[vabarbosa]

hello @nsthorat @pyu10055 just wanted to check to make sure you are not waiting on me or and there is no additional steps i should be taking? thank you.