Create a separate package for Application Handlers.

Author: visumickey

firebase-perf/src/main/java/com/google/firebase/perf/internal/AppStateMonitor.java renamed to firebase-perf/src/main/java/com/google/firebase/perf/application/AppStateMonitor.java

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.firebase.perf.internal;
+package com.google.firebase.perf.metrics;
 
 import androidx.annotation.StringDef;
 import java.lang.annotation.Retention;

firebase-perf/src/main/java/com/google/firebase/perf/internal/AppStateUpdateHandler.java renamed to firebase-perf/src/main/java/com/google/firebase/perf/application/AppStateUpdateHandler.java

@@ -1,9 +1,9 @@
-// Copyright 2020 Google LLC
+// Copyright 2021 Google LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
-//
 // You may obtain a copy of the License at
+//
 //      http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.firebase.perf.internal;
+package com.google.firebase.perf.application;
 
 import static com.google.common.truth.Truth.assertThat;
 import static org.mockito.ArgumentMatchers.anyString;
@@ -26,6 +26,10 @@
 import static org.mockito.MockitoAnnotations.initMocks;
 
 import com.google.firebase.perf.FirebasePerformanceTestBase;
+import com.google.firebase.perf.internal.GaugeManager;
+import com.google.firebase.perf.internal.PerfSession;
+import com.google.firebase.perf.internal.SessionAwareObject;
+import com.google.firebase.perf.internal.SessionManager;
 import com.google.firebase.perf.v1.ApplicationProcessState;
 import java.lang.ref.WeakReference;
 import org.junit.Before;