Fix selection getting lost on Android on the new arch (#335)

Author: j-piasecki

android/src/main/new_arch/MarkdownCommitHook.cpp

@@ -112,6 +112,15 @@ RootShadowNode::Unshared MarkdownCommitHook::shadowTreeWillCommit(
           // force measurement of a map buffer
           newStateData->cachedAttributedStringId = 0;
 
+          // setting -1 as the event counter makes sure that the update will be ignored by the java
+          // part of the code, which is what we want as we don't change the attributed string here
+          if (previousEventCount_.contains(nodes.textInput->getTag()) &&
+              previousEventCount_[nodes.textInput->getTag()] == stateData.mostRecentEventCount) {
+              newStateData->mostRecentEventCount = -1;
+          } else {
+              previousEventCount_[nodes.textInput->getTag()] = stateData.mostRecentEventCount;
+          }
+
           // clone the text input with the new state
           auto newNode = node.clone({
               .state =

android/src/main/new_arch/MarkdownCommitHook.h

@@ -47,6 +47,8 @@ class MarkdownCommitHook : public UIManagerCommitHook {
       textLayoutManagers_;
   std::unordered_map<facebook::react::Tag, folly::dynamic>
       previousDecoratorProps_;
+  std::unordered_map<facebook::react::Tag, int64_t>
+      previousEventCount_;
 };
 
 } // namespace livemarkdown