Ensure that ProxCheck doesn't run a callback twice.

If sensors weren't ready, the callback would be added to a list and
executed later if the check was used again. This was erroneous.

Fixes: 177675729
Test: atest SystemUITests
Change-Id: I9683167bb2c2f17c8fb10764d422e292274b171f

packages/SystemUI/src/com/android/systemui/util/sensors/ProximitySensor.java

@@ -347,6 +347,7 @@ public class ProximitySensor implements ThresholdSensor {
         public void check(long timeoutMs, Consumer<Boolean> callback) {
             if (!mSensor.isLoaded()) {
                 callback.accept(null);
+                return;
             }
             mCallbacks.add(callback);
             if (!mRegistered.getAndSet(true)) {

packages/SystemUI/tests/src/com/android/systemui/util/sensors/ProximityCheckTest.java

@@ -16,6 +16,8 @@
 
 package com.android.systemui.util.sensors;
 
+import static com.google.common.truth.Truth.assertThat;
+
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNull;
@@ -85,6 +87,29 @@ public class ProximityCheckTest extends SysuiTestCase {
         assertNull(mTestableCallback.mLastResult);
     }
 
+    @Test
+    public void testNotLoaded() {
+        mFakeProximitySensor.setSensorAvailable(false);
+
+        assertThat(mTestableCallback.mLastResult).isNull();
+        assertThat(mTestableCallback.mNumCalls).isEqualTo(0);
+
+        mProximityCheck.check(100, mTestableCallback);
+
+        assertThat(mTestableCallback.mLastResult).isNull();
+        assertThat(mTestableCallback.mNumCalls).isEqualTo(1);
+
+        mFakeProximitySensor.setSensorAvailable(true);
+
+        mProximityCheck.check(100, mTestableCallback);
+
+        mFakeProximitySensor.setLastEvent(new ProximitySensor.ThresholdSensorEvent(true, 0));
+        mFakeProximitySensor.alertListeners();
+
+        assertThat(mTestableCallback.mLastResult).isNotNull();
+        assertThat(mTestableCallback.mNumCalls).isEqualTo(2);
+    }
+
     @Test
     public void testProxDoesntCancelOthers() {
         assertFalse(mFakeProximitySensor.isRegistered());