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

ui/android/window_android.h

Index: ui/android/window_android.h
diff --git a/ui/android/window_android.h b/ui/android/window_android.h
index b55ba16cfa2c4cd36cddf0ad33951e98363326fa..6e767663577b1204579b6e8295f1b64e14316696 100644
--- a/ui/android/window_android.h
+++ b/ui/android/window_android.h
@@ -16,6 +16,7 @@
 #include "base/time/time.h"
 #include "ui/android/ui_android_export.h"
 #include "ui/android/view_android.h"
+#include "ui/display/display.h"
 #include "ui/gfx/geometry/vector2d_f.h"
 
 namespace ui {
@@ -27,7 +28,7 @@ class WindowAndroidObserver;
 // WindowAndroid is also the root of a ViewAndroid tree.
 class UI_ANDROID_EXPORT WindowAndroid : public ViewAndroid {
  public:
-  WindowAndroid(JNIEnv* env, jobject obj);
+  WindowAndroid(JNIEnv* env, jobject obj, int display_id);
 
   void Destroy(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
 
@@ -35,6 +36,9 @@ class UI_ANDROID_EXPORT WindowAndroid : public ViewAndroid {
 
   static bool RegisterWindowAndroid(JNIEnv* env);
 
+  // The ID of the display that this window belongs to.
+  int display_id() const { return display_id_; }

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

don't need to be public? can just friend screen_android if screen_android needs
this

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

Done.

+
   // The content offset in CSS pixels. It is used together with device scale
   // factor to translate snapshots to the correct part of the window.
   void set_content_offset(const gfx::Vector2dF& content_offset) {
@@ -45,6 +49,8 @@ class UI_ANDROID_EXPORT WindowAndroid : public ViewAndroid {
     return content_offset_;
   }
 
+  display::Display GetDisplay() const;

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

probably don't need this either

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

Removed.

+
   // Compositor callback relay.
   void OnCompositingDidCommit();
 
@@ -86,6 +92,7 @@ class UI_ANDROID_EXPORT WindowAndroid : public ViewAndroid {
   WindowAndroid* GetWindowAndroid() const override;
 
   base::android::ScopedJavaGlobalRef<jobject> java_window_;
+  int display_id_;
   gfx::Vector2dF content_offset_;
   WindowAndroidCompositor* compositor_;