[analyzer] Fix FP warnings when binding a temporary to a local static variable

Summary:
When binding a temporary object to a static local variable, the analyzer would
complain about a dangling reference even though the temporary's lifetime should
be extended past the end of the function. This commit tries to detect these
cases and construct them in a global memory region instead of a local one.

Reviewers: jordan_rose

CC: cfe-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1133

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@187196 91177308-0d34-0410-b5e6-96231b3b80d8