Sema: Create a no-op implicit cast for lvalue function conversions.

This fixes an assertion failure in the case where an implicit conversion for a
function call involves an lvalue function conversion, and makes the AST for
initializations involving implicit lvalue function conversions more accurate.

Differential Revision:

git-svn-id: 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed