Make cardreader mis-matched a special case to prompt error.

client/site_tests/hardware_Components/hardware_Components.py

Index: client/site_tests/hardware_Components/hardware_Components.py
diff --git a/client/site_tests/hardware_Components/hardware_Components.py b/client/site_tests/hardware_Components/hardware_Components.py
index e6ae5dfde01656077425fe0da1017d428548388f..91d45aa7dc32985ff5b72ea8996a48aedf905f80 100644
--- a/client/site_tests/hardware_Components/hardware_Components.py
+++ b/client/site_tests/hardware_Components/hardware_Components.py
@@ -293,7 +293,8 @@ class hardware_Components(test.test):
 
     def run_once(self, approved_dbs='approved_components', ignored_cids=[]):
         self._ignored = ignored_cids
-        all_failures = ''
+        only_cardreader_failed = False
+        all_failures = 'The following components are not matched.\n'
         os.chdir(self.bindir)
 
         # approved_dbs supports shell-like filename expansion.
@@ -325,7 +326,9 @@ class hardware_Components(test.test):
             utils.open_write_close(outdb, self.pformat(self._system))
 
             if self._failures:
-                all_failures += 'Approved DB: %s' % db
+                if self._failures.keys() == ['part_id_cardreader']:
+                    only_cardreader_failed = True
+                all_failures += 'For DB %s:' % db
                 all_failures += self.pformat(self._failures)
             else:
                 # If one of DBs is matched, record the hwqual_id and exit.
@@ -333,4 +336,8 @@ class hardware_Components(test.test):
                     {'hwqual_id': self._approved['part_id_hwqual'][0]})
                 return
 
+        if only_cardreader_failed:
+            all_failures = ('You may forget to insert an SD card.\n' +
+                            all_failures)
+
         raise error.TestFail(all_failures)