folder_branch_ops: add extra debugging for edit history flake

I can't reproduce an issue where the edit history isn't being fully
processed in a test, and haven't yet been able to deduce the cause
from an existing log, so this commit prints out the notification
messages while in test mode, so we can have more info when if it
recurs in the future.

Issue: HOTPOT-1096

go/kbfs/libkbfs/folder_branch_ops.go

@@ -9452,6 +9452,13 @@ func (fbo *folderBranchOps) getEditMessages(
 			id, err)
 		return nil
 	}
+	if fbo.config.IsTestMode() {
+		// Extra debugging for HOTPOT-1096.
+		fbo.vlog.CLogf(
+			ctx, libkb.VLog1, "%p: Got messages in channel %s: %s",
+			fbo, channelName, messages)
+	}
+
 	_, err = fbo.editHistory.AddNotifications(channelName, messages)
 	if err != nil {
 		fbo.log.CWarningf(ctx, "Couldn't add messages for conv %s: %+v",
@@ -9504,6 +9511,14 @@ func (fbo *folderBranchOps) recomputeEditHistory(
 			}
 		}
 	}
+
+	if fbo.config.IsTestMode() {
+		// Extra debugging for HOTPOT-1096.
+		fbo.vlog.CLogf(
+			ctx, libkb.VLog1, "%p: Recomputing history for %s",
+			fbo, session.Name)
+	}
+
 	// Update the overall user history.  TODO: if the TLF name
 	// changed, we should clean up the old user history.
 	fbo.config.UserHistory().UpdateHistory(
@@ -9579,6 +9594,12 @@ func (fbo *folderBranchOps) handleEditActivity(
 	}
 	if a.message != "" {
 		fbo.vlog.CLogf(ctx, libkb.VLog1, "New edit message for %s", name)
+		if fbo.config.IsTestMode() {
+			// Extra debugging for HOTPOT-1096.
+			fbo.vlog.CLogf(
+				ctx, libkb.VLog1, "%p: Processing edit message %s",
+				fbo, a.message)
+		}
 		maxRev, err := fbo.editHistory.AddNotifications(
 			name, []string{a.message})
 		if err != nil {