Make Ignition collect BinaryOperationFeedback on ToNumber, using the
shared type feedback slot with the following Inc/Dec bytecode, and use
this feedback in TurboFan to turn the ToNumber(x) operation into a
SpeculativeNumberMultiply(x,1) with the feedback hint.

R=jarin@chromium.org, mstarzinger@chromium.org, rmcilroy@chromium.org
BUG=v8:6214,v8:5267

Review-Url: https://codereview.chromium.org/2804813003
Cr-Commit-Position: refs/heads/master@{#44440}