Increase long power button press time from 8.0 to 8.2 seconds.

Some platforms (in particular Alex) don't always shut down within
the specified 8.0 seconds.  We can't fix the EC on those platforms,
so we're changing the test.

BUG=chromium-os:32266
TEST=run the test described in the bug

Change-Id: I0de58675db06fb1ff08f13058aa77d58739ee29b
Reviewed-on: https://gerrit.chromium.org/gerrit/26471
Tested-by: Richard Barnette <jrbarnette@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Commit-Ready: Richard Barnette <jrbarnette@chromium.org>
diff --git a/server/cros/servo.py b/server/cros/servo.py
index da30340..2a852ec 100644
--- a/server/cros/servo.py
+++ b/server/cros/servo.py
@@ -22,7 +22,14 @@
     """
 
     # Power button press delays in seconds.
-    LONG_DELAY = 8
+    #
+    # TODO(jrbarnette):  The EC specification says that 8.0 seconds
+    # should be enough for the long power press.  However, on
+    # existing platforms (e.g. Alex), we need a bit more time.
+    # Being generous is the right thing to do for existing platforms,
+    # but if this code is to be used for qualification of new hardware,
+    # we should be less generous.
+    LONG_DELAY = 8.2
     SHORT_DELAY = 0.1
     NORMAL_TRANSITION_DELAY = 1.2
     # Maximum number of times to re-read power button on release.