Add logs in mounting layer

Summary: Adds debug logging in FabricUIManager and the mounting layer of Fabric.

Reviewed By: shergin

Differential Revision: D14594521

fbshipit-source-id: a5c0ee39e1bac8a340849ca3e044694cbee5427e

ReactAndroid/src/main/java/com/facebook/react/fabric/FabricUIManager.java

@@ -20,6 +20,8 @@ import androidx.annotation.Nullable;
 import androidx.annotation.UiThread;
 import android.view.View;
 import com.facebook.common.logging.FLog;
+import com.facebook.debug.holder.PrinterHolder;
+import com.facebook.debug.tags.ReactDebugOverlayTags;
 import com.facebook.infer.annotation.ThreadConfined;
 import com.facebook.proguard.annotations.DoNotStrip;
 import com.facebook.react.bridge.LifecycleEventListener;
@@ -65,7 +67,9 @@ import java.util.concurrent.ConcurrentHashMap;
 @SuppressLint("MissingNativeLoadLibrary")
 public class FabricUIManager implements UIManager, LifecycleEventListener {
 
-  private static final String TAG = FabricUIManager.class.getSimpleName();
+  public static final String TAG = FabricUIManager.class.getSimpleName();
+  public static final boolean DEBUG =
+      PrinterHolder.getPrinter().shouldDisplayLogMessage(ReactDebugOverlayTags.FABRIC_UI_MANAGER);
 
   private static final Map<String, String> sComponentNames = new HashMap<>();
   private static final int FRAME_TIME_MS = 16;
@@ -161,7 +165,7 @@ public class FabricUIManager implements UIManager, LifecycleEventListener {
     mMountingManager.removeRootView(reactRootTag);
     mReactContextForRootTag.remove(reactRootTag);
   }
-  
+
   @Override
   public void initialize() {
     mEventDispatcher.registerEventEmitter(FABRIC, new FabricEventEmitter(this));

ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/mountitems/BatchMountItem.java

@@ -6,10 +6,15 @@
  */
 package com.facebook.react.fabric.mounting.mountitems;
 
+import static com.facebook.react.fabric.FabricUIManager.DEBUG;
+import static com.facebook.react.fabric.FabricUIManager.TAG;
+
 import com.facebook.proguard.annotations.DoNotStrip;
 import com.facebook.react.fabric.mounting.MountingManager;
 import com.facebook.systrace.Systrace;
 
+import com.facebook.common.logging.FLog;
+
 /**
  * This class represents a batch of {@link MountItem}s
  *
@@ -44,6 +49,9 @@ public class BatchMountItem implements MountItem {
 
     for (int mountItemIndex = 0; mountItemIndex < mSize; mountItemIndex++) {
       MountItem mountItem = mMountItems[mountItemIndex];
+      if (DEBUG) {
+        FLog.d(TAG, "Executing mountItem: " + mountItem);
+      }
       mountItem.execute(mountingManager);
     }
 

ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/mountitems/PreAllocateViewMountItem.java

@@ -6,6 +6,10 @@
  */
 package com.facebook.react.fabric.mounting.mountitems;
 
+import static com.facebook.react.fabric.FabricUIManager.DEBUG;
+import static com.facebook.react.fabric.FabricUIManager.TAG;
+
+import com.facebook.common.logging.FLog;
 import com.facebook.react.bridge.ReadableMap;
 import com.facebook.react.fabric.mounting.MountingManager;
 import com.facebook.react.uimanager.ThemedReactContext;
@@ -21,7 +25,12 @@ public class PreAllocateViewMountItem implements MountItem {
   private final boolean mIsLayoutable;
 
   public PreAllocateViewMountItem(
-      ThemedReactContext context, int rootTag, int reactTag, String component, ReadableMap props, boolean isLayoutable) {
+      ThemedReactContext context,
+      int rootTag,
+      int reactTag,
+      String component,
+      ReadableMap props,
+      boolean isLayoutable) {
     mContext = context;
     mComponent = component;
     mRootTag = rootTag;
@@ -32,11 +41,23 @@ public class PreAllocateViewMountItem implements MountItem {
 
   @Override
   public void execute(MountingManager mountingManager) {
+    if (DEBUG) {
+      FLog.d(TAG, "Executing pre-allocation of: " + toString());
+    }
     mountingManager.preallocateView(mContext, mComponent, mReactTag, mProps, mIsLayoutable);
   }
 
   @Override
   public String toString() {
-    return "[" + mRootTag + "] - Preallocate " + mComponent;
+    return "PreAllocateViewMountItem ["
+        + mReactTag
+        + "] - component: "
+        + mComponent
+        + " rootTag: "
+        + mRootTag
+        + " mIsLayoutable: "
+        + mIsLayoutable
+        + " props: "
+        + mProps;
   }
 }