exo: Refactor ShellSurface and WaylandRemoteShell

components/exo/wayland/server.cc

Index: components/exo/wayland/server.cc
diff --git a/components/exo/wayland/server.cc b/components/exo/wayland/server.cc
index 1cb7b44091b8f6860f21e207cc2f9e0187103c83..af937d13ed7c29a85b6de9be6fcf17abefbcda83 100644
--- a/components/exo/wayland/server.cc
+++ b/components/exo/wayland/server.cc
@@ -29,7 +29,6 @@
 #include <string>

[reveman, 2017/02/09 04:50:16]

I don't understand what the changes to this file are for. Please explain.

[Dominik Laskowski, 2017/02/09 23:35:28]

The code for delayed sending of display metrics was generalized to multiplex
display configuration events, i.e. multiple calls to ScheduleSendDisplayMetrics
result in one call to SendDisplayMetrics. This is used by the dependent CL to
coalesce DisplayObserver (and MaximizeModeObserver) callbacks.

 #include <utility>
 
-#include "ash/common/shell_observer.h"
 #include "ash/public/cpp/shell_window_ids.h"
 #include "ash/shell.h"
 #include "base/bind.h"
@@ -1089,8 +1088,6 @@ class WaylandPrimaryDisplayObserver : public display::DisplayObserver {
   }
 
   // Overridden from display::DisplayObserver:
-  void OnDisplayAdded(const display::Display& new_display) override {}
-  void OnDisplayRemoved(const display::Display& new_display) override {}
   void OnDisplayMetricsChanged(const display::Display& display,
                                uint32_t changed_metrics) override {
     if (display::Screen::GetScreen()->GetPrimaryDisplay().id() != display.id())
@@ -2046,7 +2043,7 @@ class WaylandRemoteShell : public WMHelper::MaximizeModeObserver,
                        ? ZCR_REMOTE_SHELL_V1_LAYOUT_MODE_TABLET
                        : ZCR_REMOTE_SHELL_V1_LAYOUT_MODE_WINDOWED;
 
-    SendPrimaryDisplayMetrics();
+    SendDisplayMetrics();
     SendActivated(helper->GetActiveWindow(), nullptr);
   }
   ~WaylandRemoteShell() override {
@@ -2068,40 +2065,29 @@ class WaylandRemoteShell : public WMHelper::MaximizeModeObserver,
   }
 
   // Overridden from display::DisplayObserver:
-  void OnDisplayAdded(const display::Display& new_display) override {}
-  void OnDisplayRemoved(const display::Display& new_display) override {}
   void OnDisplayMetricsChanged(const display::Display& display,
                                uint32_t changed_metrics) override {
     if (display::Screen::GetScreen()->GetPrimaryDisplay().id() != display.id())
       return;
 
-    // No need to update when a primary dislpay has changed without bounds
+    // No need to update when a primary display has changed without bounds
     // change. See WaylandPrimaryDisplayObserver::OnDisplayMetricsChanged
     // for more details.
     if (changed_metrics &
         (DISPLAY_METRIC_BOUNDS | DISPLAY_METRIC_DEVICE_SCALE_FACTOR |
          DISPLAY_METRIC_ROTATION | DISPLAY_METRIC_WORK_AREA)) {
-      SendDisplayMetrics(display);
+      ScheduleSendDisplayMetrics();
     }
   }
 
   // Overridden from WMHelper::MaximizeModeObserver:
   void OnMaximizeModeStarted() override {
     layout_mode_ = ZCR_REMOTE_SHELL_V1_LAYOUT_MODE_TABLET;
-
-    send_configure_after_layout_change_ = true;
-    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
-        FROM_HERE, base::Bind(&WaylandRemoteShell::MaybeSendConfigure,
-                              weak_ptr_factory_.GetWeakPtr()),
-        base::TimeDelta::FromMilliseconds(kConfigureDelayAfterLayoutSwitchMs));
+    ScheduleSendDisplayMetrics(kConfigureDelayAfterLayoutSwitchMs);
   }
   void OnMaximizeModeEnded() override {
     layout_mode_ = ZCR_REMOTE_SHELL_V1_LAYOUT_MODE_WINDOWED;
-    send_configure_after_layout_change_ = true;
-    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
-        FROM_HERE, base::Bind(&WaylandRemoteShell::MaybeSendConfigure,
-                              weak_ptr_factory_.GetWeakPtr()),
-        base::TimeDelta::FromMilliseconds(kConfigureDelayAfterLayoutSwitchMs));
+    ScheduleSendDisplayMetrics(kConfigureDelayAfterLayoutSwitchMs);
   }
 
   // Overridden from WMHelper::ActivationObserver:
@@ -2111,27 +2097,29 @@ class WaylandRemoteShell : public WMHelper::MaximizeModeObserver,
   }
 
  private:
-  void SendPrimaryDisplayMetrics() {
-    const display::Display primary =
-        display::Screen::GetScreen()->GetPrimaryDisplay();
-
-    SendDisplayMetrics(primary);
+  void ScheduleSendDisplayMetrics(int delay_ms = 0) {
+    needs_send_display_metrics_ = true;
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE, base::Bind(&WaylandRemoteShell::SendDisplayMetrics,
+                              weak_ptr_factory_.GetWeakPtr()),
+        base::TimeDelta::FromMilliseconds(delay_ms));
   }
 
-  void MaybeSendConfigure() {
-    if (send_configure_after_layout_change_)
-      SendPrimaryDisplayMetrics();
-  }
+  void SendDisplayMetrics() {
+    if (!needs_send_display_metrics_)
+      return;
+    needs_send_display_metrics_ = false;
 
-  void SendDisplayMetrics(const display::Display& display) {
-    send_configure_after_layout_change_ = false;
+    const display::Screen* screen = display::Screen::GetScreen();
+    const display::Display primary = screen->GetPrimaryDisplay();
 
-    const gfx::Insets& work_area_insets = display.GetWorkAreaInsets();
+    gfx::Size size = primary.size();
+    const gfx::Insets& work_area_insets = primary.GetWorkAreaInsets();
 
     zcr_remote_shell_v1_send_configuration_changed(
-        remote_shell_resource_, display.size().width(), display.size().height(),
-        OutputTransform(display.rotation()),
-        wl_fixed_from_double(display.device_scale_factor()),
+        remote_shell_resource_, size.width(), size.height(),
+        OutputTransform(primary.rotation()),
+        wl_fixed_from_double(primary.device_scale_factor()),
         work_area_insets.left(), work_area_insets.top(),
         work_area_insets.right(), work_area_insets.bottom(), layout_mode_);
     wl_client_flush(wl_resource_get_client(remote_shell_resource_));
@@ -2176,7 +2164,7 @@ class WaylandRemoteShell : public WMHelper::MaximizeModeObserver,
   // The remote shell resource associated with observer.
   wl_resource* const remote_shell_resource_;
 
-  bool send_configure_after_layout_change_ = false;
+  bool needs_send_display_metrics_ = true;
 
   int layout_mode_ = ZCR_REMOTE_SHELL_V1_LAYOUT_MODE_WINDOWED;