Add lock or sleep power button behavior.

This changelist defines a new short-press button behavior,
which will lock the device or put the device to sleep if
already locked. This enables use-cases where the power button
should first return to the lock screen.

Bug: 194002900
Test: manual
Change-Id: I3098e6244563cb62facb7b0b35300e656b744c7c

services/core/java/com/android/server/policy/PhoneWindowManager.java

@@ -261,6 +261,7 @@ public class PhoneWindowManager implements WindowManagerPolicy {
     static final int SHORT_PRESS_POWER_REALLY_GO_TO_SLEEP_AND_GO_HOME = 3;
     static final int SHORT_PRESS_POWER_GO_HOME = 4;
     static final int SHORT_PRESS_POWER_CLOSE_IME_OR_GO_HOME = 5;
+    static final int SHORT_PRESS_POWER_LOCK_OR_SLEEP = 6;
 
     // must match: config_LongPressOnPowerBehavior in config.xml
     static final int LONG_PRESS_POWER_NOTHING = 0;
@@ -976,6 +977,14 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                     }
                     break;
                 }
+                case SHORT_PRESS_POWER_LOCK_OR_SLEEP: {
+                    if (keyguardOn()) {
+                        sleepDefaultDisplayFromPowerButton(eventTime, 0);
+                    } else {
+                        lockNow(null /*options*/);
+                    }
+                    break;
+                }
             }
         }
     }