Perform the transformation to <BinaryOp>Smi for Binary ops which take Smi
literals in the BytecodeGenerator. This enables us to perform the
transformation for literals on either side for commutative operations, and
Avoids having to do the check on every bytecode in the peephole optimizer.

In the process, adds Smi bytecode variants for all binary operations, adding
 - MulSmi
 - DivSmi
 - ModSmi
 - BitwiseXorSmi
 - ShiftRightLogical

BUG=v8:6194

Change-Id: If1484252f5385c16957004b9cac8bfbb1f209219
Reviewed-on: https://chromium-review.googlesource.com/466246
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44477}