xfail and skipped tests are removed from the "last-failed" cache

This accommodates the case where a failing test is marked as
skipped/failed later

_pytest/cacheprovider.py

@@ -117,7 +117,7 @@ class LFPlugin:
             return "run-last-failure: %s" % mode
 
     def pytest_runtest_logreport(self, report):
-        if report.passed and report.when == 'call':
+        if (report.when == 'call' and report.passed) or report.skipped:
             self.lastfailed.pop(report.nodeid, None)
         elif report.failed:
             self.lastfailed[report.nodeid] = True

testing/test_cache.py

@@ -460,6 +460,28 @@ class TestLastFailed(object):
         result.stdout.fnmatch_lines('*1 failed*')
         assert self.get_cached_last_failed(testdir) == ['test_xfail_strict_considered_failure.py::test']
 
+    @pytest.mark.parametrize('mark', ['mark.xfail', 'mark.skip'])
+    def test_failed_changed_to_xfail_or_skip(self, testdir, mark):
+        testdir.makepyfile('''
+            import pytest
+            def test():
+                assert 0
+        ''')
+        result = testdir.runpytest()
+        assert self.get_cached_last_failed(testdir) == ['test_failed_changed_to_xfail_or_skip.py::test']
+        assert result.ret == 1
+
+        testdir.makepyfile('''
+            import pytest
+            @pytest.{mark}
+            def test():
+                assert 0
+        '''.format(mark=mark))
+        result = testdir.runpytest()
+        assert result.ret == 0
+        assert self.get_cached_last_failed(testdir) == []
+        assert result.ret == 0
+
     def get_cached_last_failed(self, testdir):
         config = testdir.parseconfigure()
         return sorted(config.cache.get("cache/lastfailed", {}))