sizeof(kPower10ExponentTable) = 651 * sizeof(int16_t) = 1302 bytes.

Their equivalence can be confirmed by this test program:

```
const int minIncl = -342;
const int maxExcl = 309;
const int kPower10ExponentTable[] = { etc };

int Power10Exponent(int n) {
  return kPower10ExponentTable[n - minIncl];
}

int main(int argc, char** argv) {
  for (int n = minIncl; n < maxExcl; n++) {
    int formula = (217706 * n >> 16) - 63;
    int table = Power10Exponent(n);
    if (formula != table) {
      return 1;
    }
  }
  return 0;
}
```

Tested by atod_manual_test over the parse-number-fxx-test-data test
cases, with and without manually disabling the EiselLemire code path,
noting that changing the magic 217706 value causes test failures.

PiperOrigin-RevId: 478646550
Change-Id: Icaaf106f9aa36e2de057f3bc9aeddc3ae0efade6