V4: disable type inference and loop peeling for the interpreter.

V4: disable type inference and loop peeling for the interpreter.

Loop peeling is always disabled. Type inference is still enabled for
QML code, because of the static-type nature of the properties.

This speeds up crypto.js by 20%.

Change-Id: Ibf51cb36f8904d64df0793980d463451dfd361e2
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>