Removes CompilationInfo::ExpectsJSReceiverAsReceiver and the associated
debug code in full-codegen which uses it. This avoids the need to check
language_mode from CompilationInfo and will enable decoupling of
ParseInfo and CompilationInfo in a followup CL.

BUG=v8:5203

Change-Id: Ib88252408e59ef321d16d5a1dd4b2b6cea609729
Reviewed-on: https://chromium-review.googlesource.com/593954Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47018}