Add context to gfx::Screen calls in support of simultaneous desktop+ash

ui/gfx/screen_gtk.cc

Index: ui/gfx/screen_gtk.cc
diff --git a/ui/gfx/screen_gtk.cc b/ui/gfx/screen_gtk.cc
index 7b0b34c8cd06dc4a51c0f396e2653b97dbd6a854..30908ce41f1c7f6676e09c4293bf686741604fbf 100644
--- a/ui/gfx/screen_gtk.cc
+++ b/ui/gfx/screen_gtk.cc
@@ -71,90 +71,110 @@ gfx::Rect GetMonitorAreaNearestWindow(gfx::NativeView view) {
   return gfx::Rect(bounds);
 }
 
-}  // namespace
+class ScreenGtk : public gfx::Screen {
+ public:
+  ScreenGtk() {
+  }
 
-namespace gfx {
+  virtual ~ScreenGtk() {
+  }
 
-// static
-bool Screen::IsDIPEnabled() {
-  return false;
-}
+  virtual bool IsDIPEnabled() OVERRIDE {
+    return false;
+  }
 
-// static
-gfx::Point Screen::GetCursorScreenPoint() {
-  gint x, y;
-  gdk_display_get_pointer(gdk_display_get_default(), NULL, &x, &y, NULL);
-  return gfx::Point(x, y);
-}
+  virtual gfx::Point GetCursorScreenPoint() OVERRIDE {
+    gint x, y;
+    gdk_display_get_pointer(gdk_display_get_default(), NULL, &x, &y, NULL);
+    return gfx::Point(x, y);
+  }
 
-// static
-gfx::NativeWindow Screen::GetWindowAtCursorScreenPoint() {
-  GdkWindow* window = gdk_window_at_pointer(NULL, NULL);
-  if (!window)
-    return NULL;
-
-  gpointer data = NULL;
-  gdk_window_get_user_data(window, &data);
-  GtkWidget* widget = reinterpret_cast<GtkWidget*>(data);
-  if (!widget)
-    return NULL;
-  widget = gtk_widget_get_toplevel(widget);
-  return GTK_IS_WINDOW(widget) ? GTK_WINDOW(widget) : NULL;
-}
+  // Returns the window under the cursor.
+  virtual gfx::NativeWindow GetWindowAtCursorScreenPoint() OVERRIDE {
+    GdkWindow* window = gdk_window_at_pointer(NULL, NULL);
+    if (!window)
+      return NULL;
+
+    gpointer data = NULL;
+    gdk_window_get_user_data(window, &data);
+    GtkWidget* widget = reinterpret_cast<GtkWidget*>(data);
+    if (!widget)
+      return NULL;
+    widget = gtk_widget_get_toplevel(widget);
+    return GTK_IS_WINDOW(widget) ? GTK_WINDOW(widget) : NULL;
+  }
 
-// static
-gfx::Display Screen::GetDisplayNearestWindow(gfx::NativeView view) {
-  gfx::Rect bounds = GetMonitorAreaNearestWindow(view);
-  // Do not use the _NET_WORKAREA here, this is supposed to be an area on a
-  // specific monitor, and _NET_WORKAREA is a hint from the WM that generally
-  // spans across all monitors.  This would make the work area larger than the
-  // monitor.
-  // TODO(danakj) This is a work-around as there is no standard way to get this
-  // area, but it is a rect that we should be computing.  The standard means
-  // to compute this rect would be to watch all windows with
-  // _NET_WM_STRUT(_PARTIAL) hints, and subtract their space from the physical
-  // area of the display to construct a work area.
-  // TODO(oshima): Implement ID and Observer.
-  return gfx::Display(0, bounds);
-}
+  // Returns the number of displays.
+  // Mirrored displays are excluded; this method is intended to return the
+  // number of distinct, usable displays.
+  virtual int GetNumDisplays() OVERRIDE {
+    // This query is kinda bogus for Linux -- do we want number of X screens?
+    // The number of monitors Xinerama has?  We'll just use whatever GDK uses.
+    GdkScreen* screen = gdk_screen_get_default();
+    return gdk_screen_get_n_monitors(screen);
+  }
 
-// static
-gfx::Display Screen::GetDisplayNearestPoint(const gfx::Point& point) {
-  GdkScreen* screen = gdk_screen_get_default();
-  gint monitor = gdk_screen_get_monitor_at_point(screen, point.x(), point.y());
-  GdkRectangle bounds;
-  gdk_screen_get_monitor_geometry(screen, monitor, &bounds);
-  // TODO(oshima): Implement ID and Observer.
-  return gfx::Display(0, gfx::Rect(bounds));
-}
+  // Returns the display nearest the specified window.
+  virtual gfx::Display GetDisplayNearestWindow(
+      gfx::NativeView view) const OVERRIDE {
+    gfx::Rect bounds = GetMonitorAreaNearestWindow(view);
+    // Do not use the _NET_WORKAREA here, this is supposed to be an area on a
+    // specific monitor, and _NET_WORKAREA is a hint from the WM that
+    // generally spans across all monitors.  This would make the work area
+    // larger than the monitor.
+    // TODO(danakj) This is a work-around as there is no standard way to get
+    // this area, but it is a rect that we should be computing.  The standard
+    // means to compute this rect would be to watch all windows with
+    // _NET_WM_STRUT(_PARTIAL) hints, and subtract their space from the
+    // physical area of the display to construct a work area.
+    // TODO(oshima): Implement ID and Observer.
+    return gfx::Display(0, bounds);
+  }
 
-// static
-gfx::Display Screen::GetDisplayMatching(const gfx::Rect& match_rect) {
-  // TODO(thestig) Implement multi-monitor support.
-  return GetPrimaryDisplay();
-}
+  // Returns the the display nearest the specified point.
+  virtual gfx::Display GetDisplayNearestPoint(
+      const gfx::Point& point) const OVERRIDE {
+    GdkScreen* screen = gdk_screen_get_default();
+    gint monitor = gdk_screen_get_monitor_at_point(
+        screen, point.x(), point.y());
+    GdkRectangle bounds;
+    gdk_screen_get_monitor_geometry(screen, monitor, &bounds);
+    // TODO(oshima): Implement ID and Observer.
+    return gfx::Display(0, gfx::Rect(bounds));
+  }
 
-// static
-gfx::Display Screen::GetPrimaryDisplay() {
-  gfx::Rect bounds = NativePrimaryMonitorBounds();
-  // TODO(oshima): Implement ID and Observer.
-  gfx::Display display(0, bounds);
-  gfx::Rect rect;
-  if (GetScreenWorkArea(&rect)) {
-    display.set_work_area(rect.Intersect(bounds));
-  } else {
-    // Return the best we've got.
-    display.set_work_area(bounds);
+  // Returns the display that most closely intersects the provided bounds.
+  virtual gfx::Display GetDisplayMatching(
+      const gfx::Rect& match_rect) const OVERRIDE {
+    // TODO(thestig) Implement multi-monitor support.
+    return GetPrimaryDisplay();
   }
-  return display;
-}
 
-// static
-int Screen::GetNumDisplays() {
-  // This query is kinda bogus for Linux -- do we want number of X screens?
-  // The number of monitors Xinerama has?  We'll just use whatever GDK uses.
-  GdkScreen* screen = gdk_screen_get_default();
-  return gdk_screen_get_n_monitors(screen);
+  // Returns the primary display.
+  virtual gfx::Display GetPrimaryDisplay() const OVERRIDE {
+    gfx::Rect bounds = NativePrimaryMonitorBounds();
+    // TODO(oshima): Implement ID and Observer.
+    gfx::Display display(0, bounds);
+    gfx::Rect rect;
+    if (GetScreenWorkArea(&rect)) {
+      display.set_work_area(rect.Intersect(bounds));
+    } else {
+      // Return the best we've got.
+      display.set_work_area(bounds);
+    }
+    return display;
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ScreenGtk);
+};
+
+}  // namespace
+
+namespace gfx {
+
+Screen* CreateNativeScreen() {
+  return new ScreenGtk;
 }
 
 }  // namespace gfx