Simplify change

Author: tejasd

firebase-perf/src/main/java/com/google/firebase/perf/metrics/AppStartTrace.java

@@ -324,16 +324,14 @@ private void recordOnDrawFrontOfQueue() {
   }
 
   private void resolveIsStartedFromBackground() {
-    // This a fix for b/339891952 where the runnable on the background thread can run before the
-    // activity lifecycle callbacks.
+    // If the runnable hasn't run, it isn't a background start.
     if (mainThreadRunnableTime == null) {
       return;
     }
 
-    if (isStartedFromBackground
-        && (mainThreadRunnableTime.getDurationMicros() < MAX_BACKGROUND_RUNNABLE_DELAY)) {
-      // Reset it to false as it was executed pre-emptively.
-      isStartedFromBackground = false;
+    // Set it to true if the runnable ran more than 100ms prior to onActivityCreated()
+    if (mainThreadRunnableTime.getDurationMicros() >= MAX_BACKGROUND_RUNNABLE_DELAY) {
+      isStartedFromBackground = true;
     }
   }
 
@@ -633,11 +631,6 @@ Timer getOnResumeTime() {
     return onResumeTime;
   }
 
-  @VisibleForTesting
-  void setIsStartFromBackground() {
-    isStartedFromBackground = true;
-  }
-
   @VisibleForTesting
   void setMainThreadRunnableTime(Timer timer) {
     mainThreadRunnableTime = timer;

firebase-perf/src/test/java/com/google/firebase/perf/metrics/AppStartTraceTest.java

@@ -239,35 +239,12 @@ public void testDelayedAppStart() {
   }
 
   @Test
-  public void testStartFromBackground() {
-    FakeScheduledExecutorService fakeExecutorService = new FakeScheduledExecutorService();
-    AppStartTrace trace =
-        new AppStartTrace(transportManager, clock, configResolver, fakeExecutorService);
-    trace.setIsStartFromBackground();
-    trace.onActivityCreated(activity1, bundle);
-    Assert.assertNull(trace.getOnCreateTime());
-    ++currentTime;
-    trace.onActivityStarted(activity1);
-    Assert.assertNull(trace.getOnStartTime());
-    ++currentTime;
-    trace.onActivityResumed(activity1);
-    Assert.assertNull(trace.getOnResumeTime());
-    fakeExecutorService.runAll();
-    // There should be no trace sent.
-    verify(transportManager, times(0))
-        .log(
-            traceArgumentCaptor.capture(),
-            ArgumentMatchers.nullable(ApplicationProcessState.class));
-  }
-
-  @Test
-  public void testStartFromBackground_invertedOrder() {
+  public void testStartFromBackground_within100ms() {
     FakeScheduledExecutorService fakeExecutorService = new FakeScheduledExecutorService();
     Timer fakeTimer = spy(new Timer(currentTime));
     AppStartTrace trace =
         new AppStartTrace(transportManager, clock, configResolver, fakeExecutorService);
     trace.registerActivityLifecycleCallbacks(appContext);
-    trace.setIsStartFromBackground();
     trace.setMainThreadRunnableTime(fakeTimer);
 
     when(fakeTimer.getDurationMicros()).thenReturn(99L);
@@ -288,13 +265,12 @@ public void testStartFromBackground_invertedOrder() {
   }
 
   @Test
-  public void testStartFromBackground_delayedInvertedOrder() {
+  public void testStartFromBackground_moreThan100ms() {
     FakeScheduledExecutorService fakeExecutorService = new FakeScheduledExecutorService();
     Timer fakeTimer = spy(new Timer(currentTime));
     AppStartTrace trace =
         new AppStartTrace(transportManager, clock, configResolver, fakeExecutorService);
     trace.registerActivityLifecycleCallbacks(appContext);
-    trace.setIsStartFromBackground();
     trace.setMainThreadRunnableTime(fakeTimer);
 
     when(fakeTimer.getDurationMicros()).thenReturn(TimeUnit.MILLISECONDS.toMicros(100) + 1);