fix: query layer 1 gas fee oracles via direct eth_call instead of ethers Web3Provider

[cryptotavares]

Explanation

Current state: OracleLayer1GasFeeFlow and MantleLayer1GasFeeFlow call OP-stack gas price oracle contracts using an ethers Contract backed by Web3Provider. Every read through this path (contract.getL1Fee → BaseProvider.call) first awaits getNetwork() → detectNetwork(), which internally depends on zero-delay setTimeout calls: the constructor's network-detection setTimeout(…, 0), an await timer(0) inside _uncachedDetectNetwork, and the detect-network cache-clear setTimeout(…, 0).

Why it needs to change: On React Native iOS, the JS timer pump is driven by a single CADisplayLink registered in RCTDisplayLink. When the display link stops receiving ticks from the render server (backboardd), all setTimeout callbacks silently stop firing — while the app remains visually foreground-active. This happens reproducibly when a WKWebView (in-app browser) becomes the active surface. Bridgeless RN has no zero-delay fast path, so even setTimeout(…, 0) waits for a display frame that never comes. As a result, ethers' getNetwork()/detectNetwork() timers never fire, the oracle eth_call is never dispatched, updateTransactionLayer1GasFee blocks indefinitely inside addTransaction, no approval is ever created, and the dapp confirmation modal never appears. This was reported as a Sev1 in MetaMask Mobile (MetaMask/metamask-mobile#32863) and reproduced on both iOS Simulator and physical iPhone.

The fix: Replace the Contract/Web3Provider dispatch path with:

1. Interface.encodeFunctionData (from @ethersproject/abi, already an indirect dependency) to ABI-encode the calldata for getL1Fee, getOperatorFee, and tokenRatio.
2. The controller's existing rpcRequest utility, which calls provider.request directly — a plain EIP-1193 call with no timer dependency.

Layer1GasFeeFlowRequest gains a messenger field so the flows can reach rpcRequest. The fix covers both the base oracle flow (OracleLayer1GasFeeFlow: getL1Fee + getOperatorFee) and MantleLayer1GasFeeFlow (tokenRatio in transformOracleFee). The fix was validated end-to-end on a live mobile repro: after the patch, the confirmation modal appears correctly while the RN timer pump is frozen.

No new npm dependencies are introduced — @ethersproject/abi was already transitively present; @ethersproject/contracts and @ethersproject/providers are no longer imported.

References

• [Bug]: iOS in-app browser — eth_sendTransaction confirmation modal never foregrounds (personal_sign works) metamask-mobile#32863 — Sev1: dapp eth_sendTransaction confirmation modal never appears on iOS in-app browser

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

---

Note

Medium Risk
Touches the addTransaction L1 fee path and introduces a breaking shape change on Layer1GasFeeFlowRequest for any custom flows, though behavior is covered by updated tests and targets a known mobile deadlock.

Overview
Layer 1 gas fee flows no longer use ethers Contract + Web3Provider to read OP-stack and Mantle oracles. They ABI-encode getL1Fee, getOperatorFee, and tokenRatio with @ethersproject/abi and call the existing rpcRequest helper (eth_call on provider.request), avoiding ethers’ setTimeout-based network detection that can hang indefinitely on React Native iOS and block addTransaction / dapp confirmations.

Layer1GasFeeFlowRequest now carries messenger instead of provider; updateTransactionLayer1GasFee passes the messenger through and no longer resolves a provider up front. Oracle responses treat empty 0x / non-string results as errors for L1 fee and Mantle tokenRatio (operator fee still defaults to zero on failure).

@ethersproject/providers is dropped from dependencies; tests are updated to mock rpcRequest and assert eth_call payloads.

^{Reviewed by Cursor Bugbot for commit f191b5f. Bugbot is set up for automated code reviews on this repo. Configure here.}

[matthewwalsh0]

Minor, is this unnecessary in changelog since Layer1GasFeeFlowRequest isn't exposed by the package?

[matthewwalsh0]

Can we remove this at the same time since it's no longer used and encourages use of rpcRequest instead?