Pass device scale factor from display to ws.

services/ui/display/platform_screen_ozone.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SERVICES_UI_DISPLAY_PLATFORM_SCREEN_OZONE_H_
 #define SERVICES_UI_DISPLAY_PLATFORM_SCREEN_OZONE_H_
 
 #include <stdint.h>
 
 #include <set>
@@ skipping 29 matching lines @@
   void RequestCloseDisplay(int64_t display_id) override;
   int64_t GetPrimaryDisplayId() const override;
 
   // mojom::DisplayController:
   void ToggleVirtualDisplay() override;
 
  private:
   // TODO(kylechar): This struct is just temporary until we migrate
   // DisplayManager code out of ash so it can be used here.
   struct DisplayInfo {
-    DisplayInfo(int64_t new_id, const gfx::Rect& new_bounds)
-        : id(new_id), bounds(new_bounds) {}
-
-    int64_t id;
-    // The display bounds.
+    int64_t id = Display::kInvalidDisplayID;
+    // The display bounds in DIP.
     gfx::Rect bounds;
+    // Display size in DDP.
+    gfx::Size pixel_size;
+    // The display scale factor, either 1 or 2.

[rjkroege, 2016/09/21 13:23:47]

not so. it can be 1.25 yes?

And same blither about scale factor: it can be computed and not passed?

[kylechar, 2016/09/21 16:31:13]

It can sort of be 1.25. It's hard to explain without showing it?

For now I'm just ignoring 1.25 in PlatformScreen so the comment is accurate-ish.

+    float scale_factor = 1.0f;
     // The display bounds have been modified and delegate should be updated.
     bool modified = false;
     // The display has been removed and delegate should be updated.
     bool removed = false;
   };
   using CachedDisplayIterator = std::vector<DisplayInfo>::iterator;
 
   // Processes list of display snapshots and sets |removed| on any displays that
   // have been removed. Updates |primary_display_id_| if the primary display was
   // removed. Does not remove displays from |cached_displays_| or send updates
@@ skipping 17 matching lines @@
 
   // Processes list of display snapshots and adds any new displays to
   // |cached_displays_|. Updates delegate by calling OnDisplayAdded().
   void AddNewDisplays(
       const ui::DisplayConfigurator::DisplayStateList& snapshots);
 
   // Returns an iterator to the cached display with |display_id| or an end
   // iterator if there is no display with that id.
   CachedDisplayIterator GetCachedDisplayIterator(int64_t display_id);
 
+  // Converts |snapshot| into a DisplayInfo.
+  DisplayInfo DisplayInfoFromSnapshot(ui::DisplaySnapshot* snapshot);
+
   // ui::DisplayConfigurator::Observer:
   void OnDisplayModeChanged(
       const ui::DisplayConfigurator::DisplayStateList& displays) override;
   void OnDisplayModeChangeFailed(
       const ui::DisplayConfigurator::DisplayStateList& displays,
       ui::MultipleDisplayState failed_new_state) override;
 
   // mojo::InterfaceFactory<mojom::DisplayController>:
   void Create(const shell::Identity& remote_identity,
               mojom::DisplayControllerRequest request) override;
@@ skipping 15 matching lines @@
   gfx::Point next_display_origin_;
 
   mojo::BindingSet<mojom::DisplayController> bindings_;
 
   DISALLOW_COPY_AND_ASSIGN(PlatformScreenOzone);
 };
 
 }  // namespace display
 
 #endif  // SERVICES_UI_DISPLAY_PLATFORM_SCREEN_OZONE_H_