- Add Views header files in a new include/views directory.
- Add initial top-level window (CefWindow), control (CefBrowserView,
  CefLabelButton, CefMenuButton, CefPanel, CefScrollView,
  CefTextfield) and layout (CefBoxLayout, CefFlowLayout) support.
  See libcef/browser/views/view_impl.h comments for implementation
  details.
- Add Views example usage in cefclient and cefsimple and Views unit
  tests in cef_unittests. Pass the `--use-views` command-line flag to
  cefclient, cefsimple and cef_unittests to run using the Views
  framework instead of platform APIs. For cefclient and cefsimple
  this will create the browser window and all related functionality
  using the Views framework. For cef_unittests this will run all
  tests (except OSR tests) in a Views-based browser window. Views-
  specific unit tests (`--gtest_filter=Views*`) will be run even if
  the the `--use-views` flag is not specified.
- Pass the `--hide-frame` command-line flag to...