Revert r156622 "Do not construct and destruct new InputType instance if it is not used."

The change was too large to merge to a release branch.

> Do not construct and destruct new InputType instance if it is not used.
>
> Fix a bug that UI elements in multiple-fields inputs don't work after
> input.type = input.type.
> This bug is a regression by Blink r151841 [1]
>
> BaseMultipleFieldsDateAndTimeInputType destructor disconnects UI elments from
> their owners. Constructing and destructing unused
> BaseMultipleFieldDateAndTimeInputType object in HTMLInputType::updateType
> diconnected existing ownership relations build by another
> BaseMultipleFieldDateAndTimeInputType object.
>
> [1] http://src.chromium.org/viewvc/blink?revision=151841&view=revision
>
> BUG=277843
> TEST=automated

BUG=277843
TBR=keishi@chromium.org

Review URL: https://codereview.chromium.org/23475004

git-svn-id: svn://svn.chromium.org/blink/trunk@156898 bbb929c8-8fbe-4397-9dbb-9b2b20218538