swift234

add special diagnostics handling for ParenExpr: without this, we would handle
them with diagnoseGeneralFailure() which would miss out on the common cases
where the subexpr of the ParenExpr is the issue.

For example, before we would produce:

t.swift:8:8: error: could not find an overload for '&' that accepts the supplied arguments
if !(x & 4.0) {}
    ~~~^~~~~~

now we produce:

t.swift:8:6: error: binary operator '&' cannot be applied to operands of type 'Int' and 'Double'
if !(x & 4.0) {}
     ^
t.swift:8:6: note: overloads for '&' exist with these partially matching parameter lists: (Int, Int)
if !(x & 4.0) {}
     ^

also, remove some special handling for lvalues and inout from overload
diagnostics, which can't matter anymore.


Swift SVN r29661