Pass bound values in base::Bind as const values

This CL replace a static_assert() in base::Bind with "const" qualifier
check to make base::Bind simpler.

base::Bind has static_assert()s to prevent the target function from
modifying the bound variable directly. But, it uses complex templates
and is hard to read. The same check can be done by passing the values
as const ones.

BUG=554299

Review-Url: https://codereview.chromium.org/2039093002
Cr-Commit-Position: refs/heads/master@{#402059}
5 files changed