Adds a utility that makes it easier to use Arena-allocated protocol buffers

[birenroy]

With this change, operations involving complex protocol buffer messages are much more efficient.

As an example, I have used the new wrapper in EdsResourcesCacheImpl, and the benchmark (added in #45926) shows an improvement to the SetResource operation.

Before:

Run on (12 X 4500 MHz CPU s)
CPU Caches:
  L1 Data 32 KiB (x6)
  L1 Instruction 32 KiB (x6)
  L2 Unified 1024 KiB (x6)
  L3 Unified 8448 KiB (x1)
Load Average: 8.13, 5.26, 3.11
***WARNING*** CPU scaling is enabled, the benchmark real time measurements may be noisy and will incur extra overhead.
***WARNING*** ASLR is enabled, the results may have unreproducible noise in them.
----------------------------------------------------------------
Benchmark                      Time             CPU   Iterations
----------------------------------------------------------------
bmSetResource/1/1            800 ns          800 ns       978841
bmSetResource/1/10          6635 ns         6634 ns       105646
bmSetResource/10/10        66568 ns        66565 ns         9212
bmSetResource/10/100      668162 ns       668139 ns          927
bmSetResource/100/100   11704205 ns     11703982 ns           66
bmGetResource/1/1           11.1 ns         11.1 ns     64584407
bmGetResource/1/10          11.1 ns         11.1 ns     64811719
bmGetResource/10/10         12.3 ns         12.3 ns     61295787
bmGetResource/10/100        11.7 ns         11.7 ns     65544985
bmGetResource/100/100       11.1 ns         11.1 ns     63082759

After:

Run on (12 X 4500 MHz CPU s)
CPU Caches:
  L1 Data 32 KiB (x6)
  L1 Instruction 32 KiB (x6)
  L2 Unified 1024 KiB (x6)
  L3 Unified 8448 KiB (x1)
Load Average: 4.67, 3.54, 2.93
***WARNING*** CPU scaling is enabled, the benchmark real time measurements may be noisy and will incur extra overhead.
***WARNING*** ASLR is enabled, the results may have unreproducible noise in them.
----------------------------------------------------------------
Benchmark                      Time             CPU   Iterations
----------------------------------------------------------------
bmSetResource/1/1            567 ns          566 ns       962403
bmSetResource/1/10          4322 ns         4322 ns       182713
bmSetResource/10/10        39329 ns        39327 ns        13611
bmSetResource/10/100      354231 ns       354193 ns         1790
bmSetResource/100/100    4878330 ns      4877578 ns          121
bmGetResource/1/1           18.3 ns         18.3 ns     32174377
bmGetResource/1/10          14.5 ns         14.5 ns     47773715
bmGetResource/10/10         15.7 ns         15.7 ns     50116376
bmGetResource/10/100        15.1 ns         15.1 ns     57349215
bmGetResource/100/100       14.3 ns         14.3 ns     38563010

Commit Message:
Additional Description:
Risk Level:
Testing:
Docs Changes:
Release Notes:
Platform Specific Features:

[repokitteh-read-only]

As a reminder, PRs marked as draft will not be automatically assigned reviewers,
or be handled by maintainer-oncall triage.

Please mark your PR as ready when you want it to be reviewed!

🐱

Caused by: #45924 was opened by birenroy.

see: more, trace.

[birenroy]

/assign @paul-r-gall