Gate nonce-overwrite change

[CriesofCarrots]

Problem

(From #11032)
As of #10973 , a successful nonce transaction advances the nonce to the most recent blockhash from the RecentBlockhashes sysvar instead of re-overwriting that nonce with the most recent bank blockhash. We expect those hashes to be the same, but in fact that can be different in the final tick of the slot, due to this:

solana/runtime/src/bank.rs

Line 1255 in 1880621

if self.is_block_boundary(current_tick_height + 1) {

This caused a bank hash mismatch on our api nodes.

We fixed the discrepancy, but that fix needs gating due to changing the bank. Therefore the overwrite also needs gating to avoid breaking anything while nodes are upgrading.

Summary of Changes

• Pass fix_recent_blockhashes_sysvar_delay into prepare_if_nonce_account() to gate overwrite in tandem with recent_blockhashes_sysvar_delay fix

[CriesofCarrots]

v1.2 at #11079

[codecov]

Codecov Report

Merging #11081 into master will decrease coverage by 0.0%.
The diff coverage is 100.0%.

@@            Coverage Diff            @@
##           master   #11081     +/-   ##
=========================================
- Coverage    82.1%    82.1%   -0.1%     
=========================================
  Files         319      319             
  Lines       73363    73367      +4     
=========================================
- Hits        60282    60269     -13     
- Misses      13081    13098     +17