Reland of Android: support multiple displays on C++ side

ui/display/android/screen_android.h

Index: ui/display/android/screen_android.h
diff --git a/ui/display/test/test_screen.h b/ui/display/android/screen_android.h
similarity index 53%
copy from ui/display/test/test_screen.h
copy to ui/display/android/screen_android.h
index fb822f5d8dcd67e11426add22056ad13f72583b6..3304317ce1ed47b3e25991a97ccc55590884fcc2 100644
--- a/ui/display/test/test_screen.h
+++ b/ui/display/android/screen_android.h
@@ -1,53 +1,45 @@
-// Copyright 2015 The Chromium Authors. All rights reserved.
+// Copyright (c) 2016 The Chromium Authors. All rights reserved.

[boliu, 2016/10/26 17:24:20]

remove (c)

[Tima Vaisburd, 2016/10/27 07:55:58]

Gone while moving/renaming

 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef UI_DISPLAY_TEST_TEST_SCREEN_H_
-#define UI_DISPLAY_TEST_TEST_SCREEN_H_
+#include <map>
 
-#include <vector>
-
-#include "base/macros.h"
 #include "ui/display/display.h"
+#include "ui/display/display_export.h"
 #include "ui/display/screen.h"
 
 namespace display {
-namespace test {
-
-// A dummy implementation of display::Screen that contains a single
-// display::Display only. The contained Display can be accessed and modified via
-// TestScreen::display().
-//
-// NOTE: Adding and removing display::DisplayOberver's are no-ops and observers
-// will NOT be notified ever.
-class TestScreen : public Screen {
+
+class DISPLAY_EXPORT ScreenAndroid : public Screen {
  public:
-  TestScreen();
-  ~TestScreen() override;
+  ScreenAndroid();
+  ~ScreenAndroid();
 
-  Display* display() { return &display_; }
+  // Disallow copy and assign.
+  ScreenAndroid(const ScreenAndroid& rhs) = delete;
+  ScreenAndroid& operator=(const ScreenAndroid& rhs) = delete;
 
-  // display::Screen:
+  // Screen interface.
   gfx::Point GetCursorScreenPoint() override;
   bool IsWindowUnderCursor(gfx::NativeWindow window) override;
   gfx::NativeWindow GetWindowAtScreenPoint(const gfx::Point& point) override;
+
   int GetNumDisplays() const override;
   std::vector<Display> GetAllDisplays() const override;
   Display GetDisplayNearestWindow(gfx::NativeView view) const override;
   Display GetDisplayNearestPoint(const gfx::Point& point) const override;
   Display GetDisplayMatching(const gfx::Rect& match_rect) const override;
   Display GetPrimaryDisplay() const override;
+
   void AddObserver(DisplayObserver* observer) override;
   void RemoveObserver(DisplayObserver* observer) override;
 
- private:
-  // The only display.
-  Display display_;
+  // Called from Java side.
+  void UpdateDisplay(int display_id, const Display& display);
+  void RemoveDisplay(int display_id);
 
-  DISALLOW_COPY_AND_ASSIGN(TestScreen);
+ private:
+  std::map<int, Display> displays_;

[mthiesse, 2016/10/26 14:49:49]

It looks like other platforms (like ash) keep their display mappings in the
display manager, and call into the manager. I think we should probably do the
same, and keep the mapping inside native DisplayAndroidManager.

[boliu, 2016/10/26 17:24:20]

The point here is we don't want to expose ScreenAndroid in a header file. aura
has a display manager, but I think mac and ios do not, so it's not really a
pattern.

It's probably easier to have DisplayAndroid.java talk directly to
screen_android.cc through jni. Nothing technically wrong with that, but that's
like unidiomatic jni. So... maybe move everything currently in screen_android.cc
to display_android.cc? Or move the jni stuff from java DisplayAndroid to
DisplayAndroidManager, dunno which one is easier.

[Tima Vaisburd, 2016/10/27 07:55:58]

Renamed screen_android.cc into display_android_manager.cc and moved the JNI
stuff from DisplayAndroid to DisplayAndroidManager. Now on native side
DisplayAndroidManager implements display::Screen interface and receives JNI
calls.

 };
 
-}  // namespace test
 }  // namespace display
-
-#endif  // UI_DISPLAY_TEST_TEST_SCREEN_H_