[master] fix return value for strict compiler checks

also fixed a trivial typo in a unit test

src/lib/datasrc/memory_datasrc.cc

@@ -267,6 +267,9 @@ ZoneData::getClosestNSEC(RBTreeNodeChain<Domain>& node_path,
     // This must be impossible and should be an internal bug.
     // See the description at the method declaration.
     assert(false);
+    // Even though there is an assert here, strict compilers
+    // will still need some return value.
+    return (ConstRBNodeRRsetPtr());
 }
 
 /// Maintain intermediate data specific to the search context used in

src/lib/datasrc/tests/memory_datasrc_unittest.cc

@@ -1074,7 +1074,7 @@ TEST_F(InMemoryZoneFinderTest, find) {
     findCheck();
 }
 
-TEST_F(InMemoryZoneFinderTest, findNSEC3Signe) {
+TEST_F(InMemoryZoneFinderTest, findNSEC3Signed) {
     findCheck(ZoneFinder::RESULT_NSEC3_SIGNED);
 }