This mostly affects ARMv6, but also fixes some failures on ARMv7 when
hardware integer division is not available.

- Fix a case where a CodePatcher accumulates literal pool entries, but
  does not actually emit them.
- Don't treat division as safe if we can't use the hardware instruction.
  Our fallback implementation returns the wrong result if the divisor is
  zero.
- Support deoptimization tables bigger than 8 bits. (kMaxNumberOfEntries
  requires a 16-bit table index.)
- Correct a TurboFan instruction encoding to encode the Operand2 mode.

BUG=

Review-Url: https://codereview.chromium.org/2021343002
Cr-Commit-Position: refs/heads/master@{#36636}