_get_main_color: skip cache for last item

Handle random order in test for py35.

Author: blueyed

src/_pytest/terminal.py

@@ -1020,7 +1020,7 @@ def show_skipped(lines: List[str]) -> None:
                 self.write_line(line)
 
     def _get_main_color(self) -> Tuple[str, List[str]]:
-        if self._main_color is None or self._known_types is None:
+        if self._main_color is None or self._known_types is None or self._is_last_item:
             self._set_main_color()
             assert self._main_color
             assert self._known_types

testing/test_terminal.py

@@ -1705,6 +1705,18 @@ def test_foobar(i): raise ValueError()
             ]
         )
 
+        # Only xfail should have yellow progress indicator.
+        result = testdir.runpytest("test_axfail.py")
+        result.stdout.re_match_lines(
+            [
+                line.format(**RE_COLORS)
+                for line in [
+                    r"test_axfail.py {yellow}x{reset}{yellow} \s+ \[100%\]{reset}",
+                    r"^{yellow}=+ ({yellow}{bold}|{bold}{yellow})1 xfailed{reset}{yellow} in ",
+                ]
+            ]
+        )
+
     def test_count(self, many_tests_files, testdir):
         testdir.makeini(
             """