Fix for copying large chunks of text

Selecting and copying a large chunk of text places a single dash into clipboard.

This is related to line 1285, where the input's content is trimmed for performance:

https://github.com/codemirror/CodeMirror/blob/mobile/lib/codemirror.js#L1285

    minimal = hasCopyEvent &&
      (range.to().line - range.from().line > 100 || (selected = cm.getSelection()).length > 1000);
    var content = minimal ? "-" : selected || cm.getSelection();

The problem is apparently a typo during refactoring/renaming from 'd' on the master branch to 'input' here.