BREAKING: Better TextInput: `contentSize` property was removed from `<TextInput>.onChange` event (Second attempt)

Summary:
`contentSize` was removed from both iOS and Android, tests was updated.
USE `onContentSizeChange` INSTEAD.

Why?
 * It always was a hack;
 * We already have dedicated event for it: `onContentSizeChange`;
 * `onChange` has nothing to do with layout actually;
 * We have to maintain `onChange` handler as fast and simple as possible, this feature complicates it a lot;
 * It was undocumented feature;
 * We already have native auto-expandable <TextInput>, so it illuminates 99% current use cases of this feature.

Reviewed By: mmmulani

Differential Revision: D4989881

fbshipit-source-id: 674bb98c89ada1fca7b3b20b304736b2a3b8304e

Libraries/Text/RCTTextView.m

@@ -30,8 +30,6 @@
   NSAttributedString *_pendingAttributedText;
 
   UITextRange *_previousSelectionRange;
-  NSUInteger _previousTextLength;
-  CGFloat _previousContentHeight;
   NSString *_predictedText;
 
   BOOL _blockTextShouldChange;
@@ -490,31 +488,12 @@ static BOOL findMismatch(NSString *first, NSString *second, NSRange *firstRange,
   _nativeUpdatesInFlight = NO;
   _nativeEventCount++;
 
-  // TODO: t16435709 This part will be removed soon.
   if (!self.reactTag || !_onChange) {
     return;
   }
 
-  // When the context size increases, iOS updates the contentSize twice; once
-  // with a lower height, then again with the correct height. To prevent a
-  // spurious event from being sent, we track the previous, and only send the
-  // update event if it matches our expectation that greater text length
-  // should result in increased height. This assumption is, of course, not
-  // necessarily true because shorter text might include more linebreaks, but
-  // in practice this works well enough.
-  NSUInteger textLength = textView.text.length;
-  CGFloat contentHeight = textView.contentSize.height;
-  if (textLength >= _previousTextLength) {
-    contentHeight = MAX(contentHeight, _previousContentHeight);
-  }
-  _previousTextLength = textLength;
-  _previousContentHeight = contentHeight;
   _onChange(@{
     @"text": self.text,
-    @"contentSize": @{
-      @"height": @(contentHeight),
-      @"width": @(textView.contentSize.width)
-    },
     @"target": self.reactTag,
     @"eventCount": @(_nativeEventCount),
   });

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

@@ -23,20 +23,14 @@ public class ReactTextChangedEvent extends Event<ReactTextChangedEvent> {
   public static final String EVENT_NAME = "topChange";
 
   private String mText;
-  private float mContentWidth;
-  private float mContentHeight;
   private int mEventCount;
 
   public ReactTextChangedEvent(
       int viewId,
       String text,
-      float contentSizeWidth,
-      float contentSizeHeight,
       int eventCount) {
     super(viewId);
     mText = text;
-    mContentWidth = contentSizeWidth;
-    mContentHeight = contentSizeHeight;
     mEventCount = eventCount;
   }
 
@@ -53,13 +47,7 @@ public class ReactTextChangedEvent extends Event<ReactTextChangedEvent> {
   private WritableMap serializeEventData() {
     WritableMap eventData = Arguments.createMap();
     eventData.putString("text", mText);
-
-    WritableMap contentSize = Arguments.createMap();
-    contentSize.putDouble("width", mContentWidth);
-    contentSize.putDouble("height", mContentHeight);
-    eventData.putMap("contentSize", contentSize);
     eventData.putInt("eventCount", mEventCount);
-
     eventData.putInt("target", getViewTag());
     return eventData;
   }

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

@@ -672,26 +672,12 @@ public class ReactTextInputManager extends BaseViewManager<ReactEditText, Layout
         return;
       }
 
-      // TODO: remove contentSize from onTextChanged entirely now that onChangeContentSize exists?
-      int contentWidth = mEditText.getWidth();
-      int contentHeight = mEditText.getHeight();
-
-      // Use instead size of text content within EditText when available
-      if (mEditText.getLayout() != null) {
-        contentWidth = mEditText.getCompoundPaddingLeft() + mEditText.getLayout().getWidth() +
-          mEditText.getCompoundPaddingRight();
-        contentHeight = mEditText.getCompoundPaddingTop() + mEditText.getLayout().getHeight() +
-          mEditText.getCompoundPaddingBottom();
-      }
-
       // The event that contains the event counter and updates it must be sent first.
       // TODO: t7936714 merge these events
       mEventDispatcher.dispatchEvent(
           new ReactTextChangedEvent(
               mEditText.getId(),
               s.toString(),
-              PixelUtil.toDIPFromPixel(contentWidth),
-              PixelUtil.toDIPFromPixel(contentHeight),
               mEditText.incrementAndGetEventCounter()));
 
       mEventDispatcher.dispatchEvent(