Fix: mostRecentEventCount is not updated. (#17990)

Summary:
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Update it's value as it changes on the JS thread, so that updated value is used (https://github.com/facebook/react-native/blob/f7f5dc66493ad25a85927a9503728b0491c8aab9/ReactAndroid/src/main/java/com/facebook/react/views/textinput/ReactEditText.java#L243) whenever setSelection(int start, int end) is called (https://github.com/facebook/react-native/blob/f7f5dc66493ad25a85927a9503728b0491c8aab9/ReactAndroid/src/main/java/com/facebook/react/views/textinput/ReactEditText.java#L315).
Pull Request resolved: https://github.com/facebook/react-native/pull/17990

Differential Revision: D14255969

Pulled By: mdvacca

fbshipit-source-id: 555d6752eabca5c31c1762955a56f99cc1828546

ReactAndroid/src/main/java/com/facebook/react/views/textinput/ReactEditText.java

@@ -236,6 +236,10 @@ public class ReactEditText extends EditText {
     mContentSizeWatcher = contentSizeWatcher;
   }
 
+  public void setMostRecentEventCount(int mostRecentEventCount) {
+    mMostRecentEventCount = mostRecentEventCount;
+  }
+
   public void setScrollWatcher(ScrollWatcher scrollWatcher) {
     mScrollWatcher = scrollWatcher;
   }

ReactAndroid/src/main/java/com/facebook/react/views/textinput/ReactTextInputManager.java

@@ -408,6 +408,11 @@ public class ReactTextInputManager extends BaseViewManager<ReactEditText, Layout
     } catch (IllegalAccessException ex) {}
   }
 
+  @ReactProp(name= "mostRecentEventCount", defaultInt = 0)
+  public void setMostRecentEventCount(ReactEditText view, int mostRecentEventCount) {
+    view.setMostRecentEventCount(mostRecentEventCount);
+  }
+
   @ReactProp(name = "caretHidden", defaultBoolean = false)
   public void setCaretHidden(ReactEditText view, boolean caretHidden) {
     view.setCursorVisible(!caretHidden);