Add Contains() to GRStateTrait's specialization of ImmutableList

[llvmbot]

Bugzilla Link	10307
Resolution	FIXED
Resolved on	Jul 14, 2011 22:33
Version	trunk
OS	All
Attachments	patch
Reporter	LLVM Bugzilla Contributor
CC	@tkremenek

Extended Description

Now that we ImmutableList has a contains() method, we can add this.

[llvmbot]

assigned to @tkremenek

[tkremenek]

Applied in r135241.