Add implementation for GetRestoredBounds for DesktopWindowTreeHostPlatform

This CL introduces SetRestoredBoundsInPixels/GetRestoredBoundsInPixels
in PlatformWindow to communicate with DesktopWindowTreeHostPlatform
and makes DesktopWindowTreeHostPlatform use PlatformWindow::
GetRestoredBoundsInPixels() to get restored bounds.

When WaylandWindow is created, HandleSurfaceConfigure() is always
called without any state setting and |state_| is normal at first.
In order to know the right time when the state is changed, this
patch also updates the initial value for |state_| of WaylandWindow
to 'PLATFORM_WINDOW_STATE_NORMAL'. With this, it clears
|restored_bounds_| correctly.

--ozone-platform=wayland --in-process-gpu, see crbug.com/848131
for more details.

Test: ozone_unittests and manual testing with ./out/ozone/chrome
Bug: 848131, 578890
Change-Id: Ifc27e60e24865a2237a0a49d5dc0f1452702c716
Reviewed-on: https://chromium-review.googlesource.com/1080354
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Julie Jeongeun Kim <jkim@igalia.com>
Cr-Commit-Position: refs/heads/master@{#582041}
16 files changed