The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d768e9a95f246bbe36f72244fdc6be15dcc99387

commit d768e9a95f246bbe36f72244fdc6be15dcc99387
Author: kylechar <kylechar@chromium.org>
Date: Fri Sep 23 22:47:44 2016

Pass device scale factor from display to ws in mustash.

Pass extra info from PlatfromScreen to it's delegate so that the device
bounds in DIP, the pixel size and device scale factor are available. The
the delegate happens to be the WS and it will use this information to
support high-DPI displays.

Most of the changes inside PlatformScreenOzone are throw away.
ash::DisplayManager already has this logic. We still have to finish
separating ash::DisplayManager from the rest of ash though,
necessitating a bit of code duplication until then.

The bounds of the display are in DIP. This is the format that is
expected from clients that receive the bounds via ScreenMus. The pixel
size of the display is needed for creating the PlatformWindow.

With this change mustash should run in high-DPI mode when running on a
device with a high-DPI internal display. It can also be enabled by
specifying the DPI for the fake display in Ozone X11, for example
--screen-config=800x800^300 will be high-DPI.

BUG= 649008 

Review-Url: https://codereview.chromium.org/2356913002
Cr-Commit-Position: refs/heads/master@{#420757}

[add] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/display/OWNERS
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/display/platform_screen_delegate.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/display/platform_screen_ozone.cc
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/display/platform_screen_ozone.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/display/platform_screen_ozone_unittests.cc
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/display/platform_screen_stub.cc
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/BUILD.gn
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/display.cc
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/display.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/display_manager.cc
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/display_manager.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/frame_generator.cc
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/frame_generator_delegate.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/platform_display.cc
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/platform_display.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/platform_display_delegate.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/platform_display_init_params.cc
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/platform_display_init_params.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/test_utils.cc
[add] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/viewport_metrics.h
[modify] https://crrev.com/d768e9a95f246bbe36f72244fdc6be15dcc99387/services/ui/ws/window_tree_host_factory.cc