Change default temp threshold to use shutdown temp

Base the temp threshold to be based on the shutdown temp lowered
by some amount to ensure the warning can be seen before a shutdown.

Test: runtest systemui
Change-Id: I033a776e874d76018592954932ed5127e1b228ae
Fixes: 62845934
diff --git a/packages/SystemUI/res/values/config.xml b/packages/SystemUI/res/values/config.xml
index 30b1692..a077fdb 100644
--- a/packages/SystemUI/res/values/config.xml
+++ b/packages/SystemUI/res/values/config.xml
@@ -328,9 +328,13 @@
     <integer name="config_showTemperatureWarning">0</integer>
 
     <!-- Temp at which to show a warning notification if config_showTemperatureWarning is true.
-         If < 0, uses the value from HardwarePropertiesManager#getDeviceTemperatures. -->
+         If < 0, uses the value from
+         HardwarePropertiesManager#getDeviceTemperatures - config_warningTemperatureTolerance. -->
     <integer name="config_warningTemperature">-1</integer>
 
+    <!-- Fudge factor for how much below the shutdown temp to show the warning. -->
+    <integer name="config_warningTemperatureTolerance">2</integer>
+
     <!-- Accessibility actions -->
     <item type="id" name="action_split_task_to_left" />
     <item type="id" name="action_split_task_to_right" />