Make Page Visibility API work when the browser window is visible or not

ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc

 // Copyright (c) 2012 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.
 
 #include "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
 
 #include <X11/extensions/shape.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/Xatom.h>
 #include <X11/Xregion.h>
@@ skipping 1232 matching lines @@
   // called by PropertyNofify event from DispatchEvent() when the browser is
   // minimized or shown from minimized state. On Windows, this is realized by
   // calling OnHostResized() with an empty size. In particular,
   // HWNDMessageHandler::GetClientAreaBounds() returns an empty size when the
   // window is minimized. On Linux, returning empty size in GetBounds() or
   // SetBounds() does not work.
   // We also propagate the minimization to the compositor, to makes sure that we
   // don't draw any 'blank' frames that could be noticed in applications such as
   // window manager previews, which show content even when a window is
   // minimized.
   bool is_minimized = IsMinimized();

[sadrul, 2015/02/23 21:43:33]

Can this be fixed/made cleverer to work correctly for
minimized/different-workspace cases?

[joone, 2015/02/23 23:26:18]

The Page Visibility API only works for minimizing/restoring a window without any
change so we don't need to handle VisibilityNotify events that are duplicated
events for minimize/restore case. I will update my patch.

   if (is_minimized != was_minimized) {
     if (is_minimized) {
       compositor()->SetVisible(false);
       content_window_->Hide();
     } else {
       content_window_->Show();
       compositor()->SetVisible(true);
     }
   }
 
@@ skipping 444 matching lines @@
           break;
         }
         case ui::ET_UNKNOWN:
           // No event is created for X11-release events for mouse-wheel buttons.
           break;
         default:
           NOTREACHED() << event_type;
       }
       break;
     }
+    case VisibilityNotify:
+      // Allows to trigger visibilityChange events when the browser window
+      // is minimized or restored.
+      if (xev->xvisibility.state == VisibilityFullyObscured)
+         content_window_->SetPageVisibility(false);
+      else
+         content_window_->SetPageVisibility(true);
+      break;
     case FocusOut:
       if (xev->xfocus.mode != NotifyGrab) {
         ReleaseCapture();
         OnHostLostWindowCapture();
         X11DesktopHandler::get()->ProcessXEvent(xev);
       } else {
         dispatcher()->OnHostLostMouseGrab();
       }
       break;
     case FocusIn:
@@ skipping 12 matching lines @@
         XTranslateCoordinates(xdisplay_, xwindow_, x_root_window_,
             0, 0, &translated_x, &translated_y, &unused);
       }
       gfx::Rect bounds(translated_x, translated_y,
                        xev->xconfigure.width, xev->xconfigure.height);
       bool size_changed = bounds_.size() != bounds.size();
       bool origin_changed = bounds_.origin() != bounds.origin();
       previous_bounds_ = bounds_;
       bounds_ = bounds;
 
-      if (origin_changed)
+      if (origin_changed) {
         OnHostMoved(bounds_.origin());
+        // Allows to trigger visibilityChange events while swithcing between
+        // workspaces.
+        ::Screen* screen = DefaultScreenOfDisplay(xdisplay_);
+        int screen_width = WidthOfScreen(screen);
+        int screen_height = HeightOfScreen(screen);
+
+        if (translated_x < 0 || translated_x > screen_width ||
+            translated_y < 0 || translated_y > screen_height)
+          content_window_->SetPageVisibility(false);
+        else
+          content_window_->SetPageVisibility(true);
+      }
 
       if (size_changed) {
         delayed_resize_task_.Reset(base::Bind(
             &DesktopWindowTreeHostX11::DelayedResize,
             close_widget_factory_.GetWeakPtr(),
             bounds.size()));
         base::MessageLoop::current()->PostTask(
             FROM_HERE, delayed_resize_task_.callback());
       }
       break;
@@ skipping 185 matching lines @@
   if (linux_ui) {
     ui::NativeTheme* native_theme = linux_ui->GetNativeTheme(window);
     if (native_theme)
       return native_theme;
   }
 
   return ui::NativeTheme::instance();
 }
 
 }  // namespace views