Make TypingCommand::insertText() to take SelectionInDOMTree instead of VisibleSelection

This patch makes |TypingCommand::insertText()| to take |SelectionInDOMTree|
instead of |VisibleSelection| to reduce usage of |VisibleSelection| for
improving code health.

BUG=657237
TEST=n/a

Review-Url: https://codereview.chromium.org/2733183002
Cr-Commit-Position: refs/heads/master@{#455368}
TriState Editor::selectionHasStyle(CSSPropertyID propertyID,
                                   const String& value) const {
  return EditingStyle::create(propertyID, value)
      ->triStateOfStyle(
          frame().selection().computeVisibleSelectionInDOMTreeDeprecated());
}

TriState Editor::selectionHasStyle(CSSPropertyID propertyID,
                                   const String& value) const {
  return EditingStyle::create(propertyID, value)
      ->triStateOfStyle(
          frame().selection().computeVisibleSelectionInDOMTreeDeprecated());
}
