ARCAnalysis: fix canNeverUseObject to correctly handle builtins.
This analysis helper was inverting the result for builtins. Builtins
such as "copyMemory" were treated as never using a value.
This manifested in a crash in TestFoundation. NSDictionary's
initializer released the incoming array before copying it. This
crashed later during dictionary destruction.
The crash was hidden by a secondary bug in mayHaveSymmetricInterference
that effectively ignored the result from canNeverUseValue.
Rename the helper to canUseObject, invert the result for builtins, and
fix mayHaveSymmetricInterference to respect the result of
canUseObject.
Note that instructions that cannot access a referenced object
obviously cannot not "interfere" with a release.
Fixing these bugs now allows ARC optimization around dealloc_stack and
other operations that don't care about the reference count.
