fix: cp-7.42.0Tokens screen performance degradation

[gambinish]

Description

Over the past couple of versions, we've seen a continued regression to Android performance. This was particularly noticeable when navigating quickly throughout the app, specifically on Samsung and Xaomi devices. We also noticed issues where the TokenList would freeze and become unresponsive.

After troubleshooting with the mobile team and QA, I think we can narrow this down to (at least) two things:

1. Tokens screen over-rendering
2. React context mounting/unmounting unnecessarily

The following two changes are being introduced in this PR:

Memoizing selectors on Tokens screen to optimize rendering with createDeepEqualSelector

• This helps to memoize data from state, to avoid React from de-referencing and causing unnecessary re-renders. useSelector only creates a shallow copy, which may often lead to undesirable behavior.

Moving AssetsPollingProvider lower down in the component hierarchy

• This polling provider initializes polling loops in core, for controllers that extend StaticIntervalPollingController (this includes the EVM assets controllers). The idea behind these polling loops is to only start them for components that need the data polled (ie be UI based)
• But currently, this context provider wraps our main nav component. This means that on each navigation, it would unmount/remount the context and re-initialize polling loops unnecessarily.

While this is a good start, I think that we should continue to expand/refine these changes to optimize performance further in future versions.

Related issues

Partially fixes: #13850

Manual testing steps

1. Launch the android app with an imported wallet with assets (tokens, NFTs)
2. Add BSC to your network list. Notice the sluggish behavior
3. Now filter by popular networks. Notice how interacting with the wallet is more sluggish
4. Try adding a token like “PEPE” while on BSC. Notice the slugish behavior

Screenshots/Recordings

Before

https://www.loom.com/share/b5c33532e7354a48ba481814dd5fa01c?sid=dd25d6af-5239-4fe4-b113-dc0ebb6e25b7

After

https://www.loom.com/share/2fb837e3607a4e9dba1239555d6b488a?sid=cf8d437d-9ab2-4272-862e-19e5b6eb17df

Pre-merge author checklist

• I’ve followed MetaMask Contributor Docs and MetaMask Mobile Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

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[github-actions]

Bitrise

🔄🔄🔄 pr_smoke_e2e_pipeline started on Bitrise...🔄🔄🔄

Commit hash: a27d934
Build link: https://app.bitrise.io/app/be69d4368ee7e86d/pipelines/21d8368d-cfa8-4dca-9f41-b00fae7872f8

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[github-actions]

Bitrise

✅✅✅ pr_smoke_e2e_pipeline passed on Bitrise! ✅✅✅

Commit hash: 9eb8385
Build link: https://app.bitrise.io/app/be69d4368ee7e86d/pipelines/8bc36f43-d724-43de-af7d-cbd0f7420b2f

Note

• You can kick off another pr_smoke_e2e_pipeline on Bitrise by removing and re-applying the Run Smoke E2E label on the pull request

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
66.7% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud