c++: __FUNCTION__ in lambda return type [PR118629]

c++: __FUNCTION__ in lambda return type [PR118629]

In this testcase, the use of __FUNCTION__ is within a function parameter
scope, the lambda's.  And P1787 changed __func__ to live in the parameter
scope.  But [basic.scope.pdecl] says that the point of declaration of
__func__ is immediately before {, so in the trailing return type it isn't in
scope yet, so this __FUNCTION__ should refer to foo().

Looking first for a block scope, then a function parameter scope, gives us
the right result.

	PR c++/118629

gcc/cp/ChangeLog:

	* name-lookup.cc (pushdecl_outermost_localscope): Look for an
	sk_block.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp0x/lambda/lambda-__func__3.C: New test.