Convert the AttrBuilder into a list of Attributes instead of one Attribute object that holds all of its attributes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173742 91177308-0d34-0410-b5e6-96231b3b80d8
Use an AttrBuilder to generate the correct AttributeSet.

We no longer accept an encoded integer as representing all of the
attributes. Convert this via the AttrBuilder class into an AttributeSet with the
correct representation (an AttributeSetImpl that holds a list of Attribute
objects).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173750 91177308-0d34-0410-b5e6-96231b3b80d8