Make InputType and InputTypeView RefCounted.

This is a preparation to add HTMLInputElement::m_inputTypeView. Both of
m_inputType and m_inputTypeView will be able to own single InputType object.

BUG=274205
TEST=none; no behavior changes.

Review URL: https://chromiumcodereview.appspot.com/23502003

git-svn-id: svn://svn.chromium.org/blink/trunk@156800 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Refactoring: Editor::frame() should return a reference.

Also, Editor::Editor and SpellCheckRequester::SpellCheckRequester shold take
reference arguments, and SpellCheckRequester::m_frame should be a referance.

BUG=none
TEST=none; no behavior changes.

Review URL: https://chromiumcodereview.appspot.com/23530002

git-svn-id: svn://svn.chromium.org/blink/trunk@156801 bbb929c8-8fbe-4397-9dbb-9b2b20218538