Fix a race in setExplicitHealthCheckEnabled() (4/n)

Sometimes the property change callback is not called within the
sleep timeout. Let's call updateConfigs() to apply device config
changes immediately to eliminate the race condition.

Bug: 178675924
Test: atest PackageWatchdogTest
Change-Id: I2b3ce79eac36cfc5ef98a62750142bb6d936e043

services/core/java/com/android/server/PackageWatchdog.java

@@ -994,7 +994,8 @@ public class PackageWatchdog {
      * Health check is enabled or disabled after reading the flags
      * from DeviceConfig.
      */
-    private void updateConfigs() {
+    @VisibleForTesting
+    void updateConfigs() {
         synchronized (mLock) {
             mTriggerFailureCount = DeviceConfig.getInt(
                     DeviceConfig.NAMESPACE_ROLLBACK,

tests/PackageWatchdog/src/com/android/server/PackageWatchdogTest.java

@@ -98,6 +98,8 @@ public class PackageWatchdogTest {
     private final TestClock mTestClock = new TestClock();
     private TestLooper mTestLooper;
     private Context mSpyContext;
+    // Keep track of all created watchdogs to apply device config changes
+    private List<PackageWatchdog> mAllocatedWatchdogs;
     @Mock
     private ConnectivityModuleConnector mConnectivityModuleConnector;
     @Mock
@@ -166,12 +168,15 @@ public class PackageWatchdogTest {
         DeviceConfig.setProperty(DeviceConfig.NAMESPACE_ROLLBACK,
                 PackageWatchdog.PROPERTY_WATCHDOG_TRIGGER_FAILURE_COUNT,
                 Integer.toString(PackageWatchdog.DEFAULT_TRIGGER_FAILURE_COUNT), false);
+
+        mAllocatedWatchdogs = new ArrayList<>();
     }
 
     @After
     public void tearDown() throws Exception {
         dropShellPermissions();
         mSession.finishMocking();
+        mAllocatedWatchdogs.clear();
     }
 
     @Test
@@ -1295,11 +1300,9 @@ public class PackageWatchdogTest {
         DeviceConfig.setProperty(DeviceConfig.NAMESPACE_ROLLBACK,
                 PackageWatchdog.PROPERTY_WATCHDOG_EXPLICIT_HEALTH_CHECK_ENABLED,
                 Boolean.toString(enabled), /*makeDefault*/false);
-        //give time for DeviceConfig to broadcast the property value change
-        try {
-            Thread.sleep(SHORT_DURATION);
-        } catch (InterruptedException e) {
-            fail("Thread.sleep unexpectedly failed!");
+        // Call updateConfigs() so device config changes take effect immediately
+        for (PackageWatchdog watchdog : mAllocatedWatchdogs) {
+            watchdog.updateConfigs();
         }
     }
 
@@ -1348,6 +1351,7 @@ public class PackageWatchdogTest {
             verify(mConnectivityModuleConnector).registerHealthListener(
                     mConnectivityModuleCallbackCaptor.capture());
         }
+        mAllocatedWatchdogs.add(watchdog);
         return watchdog;
     }