Avoid showing "Gas price extremely low" warning in advanced tab for testnets

[NiranjanaBinoy]

Fixes: #11076

Explanation:
Problem: While speeding up or canceling a transaction on testnets, the gasprice on the advanced tab is showing "Gas price extremely low" warning no matter what price is entered.

Fix: On testnets, we don't use the gas prices API to get slow, medium, and fast estimates. Instead, we just get a single estimate via eth_gasprice. So the isCustomPriceSafe() will be called only for Mainnet and e2e test and a default true value will be sent for testnets.

Manual testing steps:

• Add a custom network (e.g. https://consensys.slack.com/archives/C01CZRZ9H0T/p1618512321118000)
• Send a transaction on that network
• Try to speed up the transaction, check the advanced input tab and try adjusting the gasPrice.

[github-actions]

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[Gudahtt]

LGTM! This is at least a solid improvement.

I think there remains an issue when the gas estimation API is offline. If we don't have any value cached for the safe low price, this problem will continue to affect users on mainnet I think?

I haven't thought this through, so I don't know how we might fix that issue. If a solution isn't clear, perhaps we can open a separate issue for it, and merge this for now.

[NiranjanaBinoy]

LGTM! This is at least a solid improvement.

I think there remains an issue when the gas estimation API is offline. If we don't have any value cached for the safe low price, this problem will continue to affect users on mainnet I think?

I haven't thought this through, so I don't know how we might fix that issue. If a solution isn't clear, perhaps we can open a separate issue for it, and merge this for now.

PR #10767 is handling the gas API failure scenarios, currently, if the API fetch fails we are fetching gas price from eth_gasprice and warning the user of the same, and failure of both the service will disable the transaction submission and shows an error message.

I have updated to set customPriceIsSafe to true in the API fetch failure for speedup and cancellation. Is this a suitable solution for this problem?

[metamaskbot]

Builds ready [6d11781]

• builds: chrome, firefox, opera
• bundle viz: background, ui, inpage, contentscript, ui-libs, bg-libs, phishing-detect
• build viz: Build System
• code coverage: Report
• storybook: Storybook
• all artifacts

Page Load Metrics (584 ± 47 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	44	83	59	10	5
		domContentLoaded	359	750	583	98	47
		load	360	751	584	98	47
		domInteractive	358	750	583	98	47

[Gudahtt]

Ah, great idea! I hadn't seen this basicEstimateStatus.

Though, I think we'll need to use a different selector. This one will return false if the gas estimates are still loading for example, wrongly displaying this warning until they finish. It'll also show the warning if the gas estimates failed to load completely.

Maybe we should only show the warning if basicEstimateStatus is READY, and the estimateSource is MetaSwaps? (or not eth_gasprice, alternatively)

[metamaskbot]

Builds ready [b8d37a5]

• builds: chrome, firefox, opera
• bundle viz: background, ui, inpage, contentscript, ui-libs, bg-libs, phishing-detect
• build viz: Build System
• code coverage: Report
• storybook: Storybook
• all artifacts

Page Load Metrics (603 ± 40 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	44	80	64	11	5
		domContentLoaded	373	720	602	82	40
		load	374	721	603	82	40
		domInteractive	372	719	602	82	40

[Gudahtt]

LGTM!