[TextField] multiLine TextField loses cursor position on height change

[jamesbillinger]

A multiLine textfield (EnhancedTextarea) moves the cursor to the end of the field when a setState is called. Specifically, if you're working in the middle of a large block of text and you make a change which results in the height of the textarea changing, the cursor will move to the end of the field.

If I comment out the setState call in syncHeightWithShadow the problem disappears. I'm sure this function is needed...not sure why it's losing cursor position.

    key: 'syncHeightWithShadow',
    value: function syncHeightWithShadow(newValue, event) {
      var shadow = this.refs.shadow;

      if (newValue !== undefined) {
        shadow.value = newValue;
      }

      var newHeight = shadow.scrollHeight;

      if (this.props.rowsMax >= this.props.rows) {
        newHeight = Math.min(this.props.rowsMax * rowsHeight, newHeight);
      }

      newHeight = Math.max(newHeight, rowsHeight);

      if (this.state.height !== newHeight) {
        /*this.setState({
          height: newHeight
        });*/

        if (this.props.onHeightChange) {
          this.props.onHeightChange(event, newHeight);
        }
      }
    }

I'm using version 0.15.0-beta.2. I did not test on 0.15.0, but I looked through the changes to this file and I didn't see anything related.

Tested in Chrome and Firefox

[oliviertassinari]

Fixed by #7006.