Revert "Use Flag instead of method check to detect new message queue testability API"

This reverts commit 949e5e48020db3c8d5b3b0a2b1b3d9120cab4ad2.

Reason for revert: somehow incompatible with mainline R/S/T/U/V

https://android-build.corp.google.com/test_investigate/?blocking=blocking&status=none&invocationId=I90800010367953228&testResultId=TR09129634304861714&legacy=

java.lang.NoClassDefFoundError: android.net.connectivity.android.os.test.TestLooper
	at android.net.connectivity.com.android.server.connectivity.MulticastRoutingCoordinatorServiceTest.prepareService(MulticastRoutingCoordinatorServiceTest.kt:153)
	at android.net.connectivity.com.android.server.connectivity.MulticastRoutingCoordinatorServiceTest.testConstructor_multicastRoutingSocketIsCreated(MulticastRoutingCoordinatorServiceTest.kt:204)
	... 8 trimmed
Caused by: java.lang.NoSuchMethodError: No static method messageQueueTestability()Z in class Lcom/android/internal/hidden_from_bootclasspath/android/os/Flags; or its super classes (declaration of 'com.android.internal.hidden_from_bootclasspath.android.os.Flags' appears in /system/framework/framework.jar!classes4.dex)
	at android.net.connectivity.android.os.test.TestLooper.newTestabilityApisSupported(TestLooper.java:71)
	at android.net.connectivity.android.os.test.TestLooper.<clinit>(TestLooper.java:84)
	at android.net.connectivity.com.android.server.connectivity.MulticastRoutingCoordinatorServiceTest.prepareService(MulticastRoutingCoordinatorServiceTest.kt:153)
	at android.net.connectivity.com.android.server.connectivity.MulticastRoutingCoordinatorServiceTest.testMulticastRouting_applyForwardNone(MulticastRoutingCoordinatorServiceTest.kt:210)
	... 9 more

Change-Id: I40192ddd4366792b6d8742826e575b2569337c85

2 files changed, 38 insertions, 25 deletions

diff --git a/tests/testables/src/android/testing/TestableLooper.java b/tests/testables/src/android/testing/TestableLooper.java
index 7a19add1d1b9..8cd89ce89e83 100644
--- a/tests/testables/src/android/testing/TestableLooper.java
+++ b/tests/testables/src/android/testing/TestableLooper.java
@@ -34,6 +34,7 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 import java.lang.reflect.Field;
+import java.lang.reflect.Method;
 import java.util.ArrayDeque;
 import java.util.Map;
 import java.util.Objects;
@@ -73,15 +74,21 @@ public class TestableLooper {
     /**
      * Baklava introduces new {@link TestLooperManager} APIs that we can use instead of reflection.
      */
-    private static boolean newTestabilityApisSupported() {
-        return android.os.Flags.messageQueueTestability();
+    private static boolean isAtLeastBaklava() {
+        Method[] methods = TestLooperManager.class.getMethods();
+        for (Method method : methods) {
+            if (method.getName().equals("peekWhen")) {
+                return true;
+            }
+        }
+        return false;
         // TODO(shayba): delete the above, uncomment the below.
         // SDK_INT has not yet ramped to Baklava in all 25Q2 builds.
         // return Build.VERSION.SDK_INT >= Build.VERSION_CODES.BAKLAVA;
     }
 
     static {
-        if (newTestabilityApisSupported()) {
+        if (isAtLeastBaklava()) {
             MESSAGE_QUEUE_MESSAGES_FIELD = null;
             MESSAGE_NEXT_FIELD = null;
             MESSAGE_WHEN_FIELD = null;
@@ -241,14 +248,14 @@ public class TestableLooper {
     }
 
     public void moveTimeForward(long milliSeconds) {
-        if (newTestabilityApisSupported()) {
-            moveTimeForwardModern(milliSeconds);
+        if (isAtLeastBaklava()) {
+            moveTimeForwardBaklava(milliSeconds);
         } else {
             moveTimeForwardLegacy(milliSeconds);
         }
     }
 
-    private void moveTimeForwardModern(long milliSeconds) {
+    private void moveTimeForwardBaklava(long milliSeconds) {
         // Drain all Messages from the queue.
         Queue<Message> messages = new ArrayDeque<>();
         while (true) {
diff --git a/tests/utils/testutils/java/android/os/test/TestLooper.java b/tests/utils/testutils/java/android/os/test/TestLooper.java
index c7a36dd3f9d8..4d379e45a81a 100644
--- a/tests/utils/testutils/java/android/os/test/TestLooper.java
+++ b/tests/utils/testutils/java/android/os/test/TestLooper.java
@@ -65,13 +65,19 @@ public class TestLooper {
     private AutoDispatchThread mAutoDispatchThread;
 
     /**
-     * Modern introduces new {@link TestLooperManager} APIs that we can use instead of reflection.
+     * Baklava introduces new {@link TestLooperManager} APIs that we can use instead of reflection.
      */
-    private static boolean newTestabilityApisSupported() {
-        return android.os.Flags.messageQueueTestability();
+    private static boolean isAtLeastBaklava() {
+        Method[] methods = TestLooperManager.class.getMethods();
+        for (Method method : methods) {
+            if (method.getName().equals("peekWhen")) {
+                return true;
+            }
+        }
+        return false;
         // TODO(shayba): delete the above, uncomment the below.
-        // SDK_INT has not yet ramped to Modern in all 25Q2 builds.
-        // return Build.VERSION.SDK_INT >= Build.VERSION_CODES.Modern;
+        // SDK_INT has not yet ramped to Baklava in all 25Q2 builds.
+        // return Build.VERSION.SDK_INT >= Build.VERSION_CODES.BAKLAVA;
     }
 
     static {
@@ -81,7 +87,7 @@ public class TestLooper {
             THREAD_LOCAL_LOOPER_FIELD = Looper.class.getDeclaredField("sThreadLocal");
             THREAD_LOCAL_LOOPER_FIELD.setAccessible(true);
 
-            if (newTestabilityApisSupported()) {
+            if (isAtLeastBaklava()) {
                 MESSAGE_QUEUE_MESSAGES_FIELD = null;
                 MESSAGE_NEXT_FIELD = null;
                 MESSAGE_WHEN_FIELD = null;
@@ -130,7 +136,7 @@ public class TestLooper {
             throw new RuntimeException("Reflection error constructing or accessing looper", e);
         }
 
-        if (newTestabilityApisSupported()) {
+        if (isAtLeastBaklava()) {
             mTestLooperManager =
                 InstrumentationRegistry.getInstrumentation().acquireLooperManager(mLooper);
         } else {
@@ -159,14 +165,14 @@ public class TestLooper {
     }
 
     public void moveTimeForward(long milliSeconds) {
-        if (newTestabilityApisSupported()) {
-            moveTimeForwardModern(milliSeconds);
+        if (isAtLeastBaklava()) {
+            moveTimeForwardBaklava(milliSeconds);
         } else {
             moveTimeForwardLegacy(milliSeconds);
         }
     }
 
-    private void moveTimeForwardModern(long milliSeconds) {
+    private void moveTimeForwardBaklava(long milliSeconds) {
         // Drain all Messages from the queue.
         Queue<Message> messages = new ArrayDeque<>();
         while (true) {
@@ -259,14 +265,14 @@ public class TestLooper {
      * @return true if there are pending messages in the message queue
      */
     public boolean isIdle() {
-        if (newTestabilityApisSupported()) {
-            return isIdleModern();
+        if (isAtLeastBaklava()) {
+            return isIdleBaklava();
         } else {
             return isIdleLegacy();
         }
     }
 
-    private boolean isIdleModern() {
+    private boolean isIdleBaklava() {
         Long when = mTestLooperManager.peekWhen();
         return when != null && currentTime() >= when;
     }
@@ -280,14 +286,14 @@ public class TestLooper {
      * @return the next message in the Looper's message queue or null if there is none
      */
     public Message nextMessage() {
-        if (newTestabilityApisSupported()) {
-            return nextMessageModern();
+        if (isAtLeastBaklava()) {
+            return nextMessageBaklava();
         } else {
             return nextMessageLegacy();
         }
     }
 
-    private Message nextMessageModern() {
+    private Message nextMessageBaklava() {
         if (isIdle()) {
             return mTestLooperManager.poll();
         } else {
@@ -308,14 +314,14 @@ public class TestLooper {
      * Asserts that there is a message in the queue
      */
     public void dispatchNext() {
-        if (newTestabilityApisSupported()) {
-            dispatchNextModern();
+        if (isAtLeastBaklava()) {
+            dispatchNextBaklava();
         } else {
             dispatchNextLegacy();
         }
     }
 
-    private void dispatchNextModern() {
+    private void dispatchNextBaklava() {
         assertTrue(isIdle());
         Message msg = mTestLooperManager.poll();
         if (msg == null) {