Fix hasFrameMetricsAggregator's value not being set.

Author: jeremyjiang-dev

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

@@ -55,6 +55,7 @@ public class AppStateMonitor implements ActivityLifecycleCallbacks {
       "androidx.core.app.FrameMetricsAggregator";
 
   private static volatile AppStateMonitor instance;
+  private static boolean hasFrameMetricsAggregator = false;
 
   private final WeakHashMap<Activity, Boolean> activityToResumedMap = new WeakHashMap<>();
   private final WeakHashMap<Activity, Trace> activityToScreenTraceMap = new WeakHashMap<>();
@@ -78,7 +79,6 @@ public class AppStateMonitor implements ActivityLifecycleCallbacks {
 
   private boolean isRegisteredForLifecycleCallbacks = false;
   private boolean isColdStart = true;
-  private boolean hasFrameMetricsAggregator = false;
 
   public static AppStateMonitor getInstance() {
     if (instance == null) {
@@ -215,7 +215,7 @@ public synchronized void onActivityResumed(Activity activity) {
     }
 
     // Screen trace is after session update so the sessionId is not added twice to the Trace
-    if (isScreenTraceSupported(activity) && configResolver.isPerformanceMonitoringEnabled()) {
+    if (isScreenTraceSupported() && configResolver.isPerformanceMonitoringEnabled()) {
       // Starts recording frame metrics for this activity.
       /**
        * TODO: Only add activities that are hardware acceleration enabled so that calling {@link
@@ -441,8 +441,10 @@ protected boolean isScreenTraceSupported() {
   private static boolean hasFrameMetricsAggregatorClass() {
     try {
       Class<?> initializerClass = Class.forName(FRAME_METRICS_AGGREGATOR_CLASSNAME);
+      hasFrameMetricsAggregator = true;
       return true;
     } catch (ClassNotFoundException e) {
+      hasFrameMetricsAggregator = false;
       return false;
     }
   }