Cleanup: Simplify expression checking has side effects in it's drop impl

Remove Option<_> from the list of type being checked as it doesn't implement Drop

Fix: Wrong default value if generic  type can't be resolved in the aforementioned expression

Author: Jarcho

clippy_lints/src/matches.rs

@@ -1755,16 +1755,15 @@ mod redundant_pattern_match {
         }
 
         // Check for std types which implement drop, but only for memory allocation.
-        !((is_type_diagnostic_item(cx, ty, sym::vec_type)
-            && !try_get_generic_ty(ty, 0).map_or(false, |ty| type_needs_ordered_drop(cx, ty)))
-            || (is_type_lang_item(cx, ty, LangItem::OwnedBox)
-                && !try_get_generic_ty(ty, 0).map_or(false, |ty| type_needs_ordered_drop(cx, ty)))
-            || (is_type_diagnostic_item(cx, ty, sym::option_type)
-                && !try_get_generic_ty(ty, 0).map_or(false, |ty| type_needs_ordered_drop(cx, ty)))
-            || (is_type_diagnostic_item(cx, ty, sym::Rc)
-                && !try_get_generic_ty(ty, 0).map_or(false, |ty| type_needs_ordered_drop(cx, ty)))
-            || (is_type_diagnostic_item(cx, ty, sym::Arc)
-                && !try_get_generic_ty(ty, 0).map_or(false, |ty| type_needs_ordered_drop(cx, ty))))
+        if is_type_diagnostic_item(cx, ty, sym::vec_type)
+            || is_type_lang_item(cx, ty, LangItem::OwnedBox)
+            || is_type_diagnostic_item(cx, ty, sym::Rc)
+            || is_type_diagnostic_item(cx, ty, sym::Arc)
+        {
+            try_get_generic_ty(ty, 0).map_or(true, |ty| type_needs_ordered_drop(cx, ty))
+        } else {
+            true
+        }
     }
 
     // Extract the generic arguments out of a type