Hack to get devices booting again.

If we try scheduling a pass before the system is ready, record a
pending event and dispatch once we're actually ready.

Bug: 26863668
Change-Id: I028285383c8bbe8b653aeaa7544eefe3d41277bc

services/usage/java/com/android/server/usage/UsageStatsService.java

@@ -145,6 +145,8 @@ public class UsageStatsService extends SystemService implements
     private boolean mScreenOn;
     private long mLastAppIdleParoledTime;
 
+    private volatile boolean mPendingOneTimeCheckIdleStates;
+
     long mScreenOnTime;
     long mLastScreenOnEventRealtime;
 
@@ -221,6 +223,10 @@ public class UsageStatsService extends SystemService implements
             synchronized (mLock) {
                 updateDisplayLocked();
             }
+
+            if (mPendingOneTimeCheckIdleStates) {
+                postOneTimeCheckIdleStates();
+            }
         } else if (phase == PHASE_BOOT_COMPLETED) {
             setAppIdleParoled(getContext().getSystemService(BatteryManager.class).isCharging());
         }
@@ -368,7 +374,13 @@ public class UsageStatsService extends SystemService implements
      * scheduling a series of repeating checkIdleStates each time we fired off one.
      */
     void postOneTimeCheckIdleStates() {
-        mHandler.sendEmptyMessage(MSG_ONE_TIME_CHECK_IDLE_STATES);
+        if (mDeviceIdleController == null) {
+            // Not booted yet; wait for it!
+            mPendingOneTimeCheckIdleStates = true;
+        } else {
+            mHandler.sendEmptyMessage(MSG_ONE_TIME_CHECK_IDLE_STATES);
+            mPendingOneTimeCheckIdleStates = false;
+        }
     }
 
     /** Check all running users' or specified user's apps to see if they enter an idle state. */