Eliminate online gas estimation from send and invite flows

[nategraf]

Description

As described in celo-org/celo-monorepo#5432, gas estimation is a costly
operation for the mobile client. The most promising short-term solution is to simply hard-code the
gas value to be used in for simple transactions along common code paths. The most common transaction
sent by a typical user is to send cUSD, either by a direct transfer or an invite.

This PR adds the required plumbing to use a single gas value, price and currency throughout the send
and invite flows. As a result, a single constant gas value can be used from start to finish. The
major result of this is that instead of estimating gas online twice, as the app currently does, the
static value is used and online gas estimation is never used.

This represents a large improvement to the experienced transaction speed, especially in less than
ideal network conditions. Additional effects of this are that errors caused by gas estimation should
be reduced, it's possible to give a fee estimate while offline, and the fee estimate shown the user
will be respected as a maximum fee value.

Other changes

• Remove the unused EstimateFee.tsx
• Refactor cancellation for sendTransaction
• Fix gas price cache to handle multiple currencies.
• Propagate receipts back up from sendTransaction
• Use a Lock for getting contractkit instance to avoid reliance on polling and flag-based locking.
• Don't clear the transaction feed when the call to the blockchain API fails, such as when the device is offline.
• Add networkConnectedSelector to access the network connectivity state reported by the device.

Tested

• Updated snapshot and unit tests to cover new functionality
• Manually tests effected user flows: Sending cUSD, escrow, and reclaiming escow

Related issues

• Related: Valora Performance: Gas estimation logic celo-org/celo-monorepo#5432

Backwards compatibility

No backwards compatibility concerns.

[nategraf]

Just noticed in the logs the following message.

[Fri Mar 12 2021 17:09:41.193]  INFO     Warning: Cannot update a component from inside the function body of a different component.%s ["
    in CalculateSendFee (at CalculateFee.tsx:138)
    in CalculateFee (at SendConfirmation.tsx:451)
    in SendConfirmation (at SceneView.tsx:122)
    in StaticContainer

I have a feeling it's related to this line below, but I'm not exactly sure what to do differently. Maybe a helpful reviewer could suggest a fix!
https://github.com/celo-org/wallet/blob/ecfa456aa4e2ba7a4b102b4b58a6aa196016b945/packages/mobile/src/send/SendConfirmation.tsx#L244

[etuleu]

Warning: Cannot update a component from inside the function body of a different component

Sounds like this: https://reactjs.org/blog/2020/02/26/react-v16.13.0.html#warnings-for-some-updates-during-render

Maybe we can fix these in a different PR though unless it's easy to make the change. It's not a huge problem for now, but we should fix these warnings at some point.

[etuleu]

I looked over the changes but for me at this point this is mostly a learning exercise. Would be good to get Jean's eyes over this as well for sure.

[ValoraQA]

Hi @nategraf I have verified this issue using Android Internal Build V1.12.0(1004294340) & observed following:
Observations:

• 4G Network: Observed that, app takes 25 sec to load sending screen with estimation after tapping on Send button. Also it is observed that more than one gas fees are displaying.
• 3G Network: Observed that, app takes more that a minute to load estimation on sending screen. Also observed user multiple fees are applied.
• 512 kbps speed:(using Charles) Observed that, continuous loading indicator displayed for longer time & user not able to proceed from Send screen after tapping on Review button.
  Verified on devices: Samsung Galaxy A5(7.0), iPhone XR (14.2)

Let me know if anything else need to test.
Thanks..!!