fix bug in dirty mount logging

Summary: There was a bug in mount event logging where mIsDirty was set to false before we logged the previous value. This diff fixes that.

Reviewed By: rohan-mehta

Differential Revision: D15393545

fbshipit-source-id: 01be8fae5610982a021056db5089e4719ee11840

litho-core/src/main/java/com/facebook/litho/MountState.java

@@ -372,6 +372,7 @@ void mount(LayoutState layoutState, Rect localVisibleRect, boolean processVisibi
 
     mRootTransition = null;
     mTransitionsHasBeenCollected = false;
+    final boolean wasDirty = mIsDirty;
     mIsDirty = false;
     mNeedsRemount = false;
     mIsFirstMountOfComponentTree = false;
@@ -388,15 +389,16 @@ void mount(LayoutState layoutState, Rect localVisibleRect, boolean processVisibi
     suppressInvalidationsOnHosts(false);
 
     if (logger != null) {
-      logMountPerfEvent(logger, mountPerfEvent);
+      logMountPerfEvent(logger, mountPerfEvent, wasDirty);
     }
 
     if (isTracing) {
       ComponentsSystrace.endSection();
     }
   }
 
-  private void logMountPerfEvent(ComponentsLogger logger, @Nullable PerfEvent mountPerfEvent) {
+  private void logMountPerfEvent(
+      ComponentsLogger logger, @Nullable PerfEvent mountPerfEvent, boolean isDirty) {
     if (!mMountStats.isLoggingEnabled || mountPerfEvent == null) {
       logger.cancelPerfEvent(mountPerfEvent);
       return;
@@ -436,7 +438,7 @@ private void logMountPerfEvent(ComponentsLogger logger, @Nullable PerfEvent moun
         PARAM_VISIBILITY_HANDLER_TIME, mMountStats.visibilityHandlerTimes.toArray(new Double[0]));
 
     mountPerfEvent.markerAnnotate(PARAM_NO_OP_COUNT, mMountStats.noOpCount);
-    mountPerfEvent.markerAnnotate(PARAM_IS_DIRTY, mIsDirty);
+    mountPerfEvent.markerAnnotate(PARAM_IS_DIRTY, isDirty);
 
     logger.logPerfEvent(mountPerfEvent);
   }