[RNMobile] Make sure the native side is refreshed after blocks Merging (

#11576)

* Make sure the new content is correctly propagated to the native side after merge.

* Fix lint

packages/editor/src/components/rich-text/index.native.js

@@ -221,12 +221,6 @@ export class RichText extends Component {
 		const empty = this.isEmpty();
 
 		if ( onMerge ) {
-			// The onMerge event can cause a content update event for this block.  Such event should
-			// definitely be processed by our native components, since they have no knowledge of
-			// how the split works.  Setting lastEventCount to undefined forces the native component to
-			// always update when provided with new content.
-			this.lastEventCount = undefined;
-
 			onMerge( ! isReverse );
 		}
 
@@ -274,14 +268,23 @@ export class RichText extends Component {
 			this.lastContent = undefined;
 			return true;
 		}
-		// The check below allows us to avoid updating the content right after an `onChange` call
-		// first time the component is drawn with empty content `lastContent` is undefined
-		if ( nextProps.value &&
+		// The check below allows us to avoid updating the content right after an `onChange` call.
+		// The first time the component is drawn `lastContent` and `lastEventCount ` are both undefined
+		if ( this.lastEventCount &&
+			nextProps.value &&
 			this.lastContent &&
-			this.lastEventCount ) {
+			nextProps.value === this.lastContent ) {
 			return false;
 		}
 
+		// If the component is changed React side (merging/splitting/custom text actions) we need to make sure
+		// the native is updated as well
+		if ( nextProps.value &&
+			this.lastContent &&
+			nextProps.value !== this.lastContent ) {
+			this.lastEventCount = undefined; // force a refresh on the native side
+		}
+
 		return true;
 	}