Decouple X11WindowEventFilter into WindowEventFilter parent class.

ui/views/widget/desktop_aura/window_event_filter.cc

Index: ui/views/widget/desktop_aura/window_event_filter.cc
diff --git a/ui/views/widget/desktop_aura/window_event_filter.cc b/ui/views/widget/desktop_aura/window_event_filter.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7215f17fe11f9b6185199973f5980ea2a871f80d
--- /dev/null
+++ b/ui/views/widget/desktop_aura/window_event_filter.cc
@@ -0,0 +1,139 @@
+// Copyright 2017 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/window_event_filter.h"
+
+#include "services/ui/public/interfaces/window_manager_constants.mojom.h"
+#include "ui/aura/client/aura_constants.h"
+#include "ui/aura/window.h"
+#include "ui/aura/window_delegate.h"
+#include "ui/aura/window_tree_host.h"
+#include "ui/base/hit_test.h"
+#include "ui/display/display.h"
+#include "ui/display/screen.h"
+#include "ui/events/event.h"
+#include "ui/events/event_utils.h"
+#include "ui/views/linux_ui/linux_ui.h"
+#include "ui/views/widget/desktop_aura/desktop_window_tree_host.h"
+#include "ui/views/widget/native_widget_aura.h"
+#include "ui/views/widget/widget.h"
+
+namespace views {
+
+WindowEventFilter::WindowEventFilter(DesktopWindowTreeHost* window_tree_host)
+    : window_tree_host_(window_tree_host), click_component_(HTNOWHERE) {}
+
+WindowEventFilter::~WindowEventFilter() {}
+
+void WindowEventFilter::OnMouseEvent(ui::MouseEvent* event) {
+  if (event->type() != ui::ET_MOUSE_PRESSED)
+    return;
+
+  aura::Window* target = static_cast<aura::Window*>(event->target());
+  if (!target->delegate())
+    return;
+
+  int previous_click_component = HTNOWHERE;
+  int component = target->delegate()->GetNonClientComponent(event->location());
+  if (event->IsLeftMouseButton()) {
+    previous_click_component = click_component_;
+    click_component_ = component;
+  }
+
+  if (component == HTCAPTION) {
+    OnClickedCaption(event, previous_click_component);
+  } else if (component == HTMAXBUTTON) {
+    OnClickedMaximizeButton(event);
+  } else {
+    if (target->GetProperty(aura::client::kResizeBehaviorKey) &
+        ui::mojom::kResizeBehaviorCanResize) {
+      MaybeDispatchHostWindowDragMovement(component, event);
+    }
+  }
+}
+
+void WindowEventFilter::OnClickedCaption(ui::MouseEvent* event,
+                                         int previous_click_component) {
+  aura::Window* target = static_cast<aura::Window*>(event->target());
+
+  if (event->IsMiddleMouseButton()) {
+    LinuxUI::NonClientMiddleClickAction action =
+        LinuxUI::MIDDLE_CLICK_ACTION_LOWER;
+    LinuxUI* linux_ui = LinuxUI::instance();
+    if (linux_ui)
+      action = linux_ui->GetNonClientMiddleClickAction();
+
+    switch (action) {
+      case LinuxUI::MIDDLE_CLICK_ACTION_NONE:
+        break;
+      case LinuxUI::MIDDLE_CLICK_ACTION_LOWER:
+        LowerWindow();
+        break;
+      case LinuxUI::MIDDLE_CLICK_ACTION_MINIMIZE:
+        window_tree_host_->Minimize();
+        break;
+      case LinuxUI::MIDDLE_CLICK_ACTION_TOGGLE_MAXIMIZE:
+        if (target->GetProperty(aura::client::kResizeBehaviorKey) &
+            ui::mojom::kResizeBehaviorCanMaximize)
+          ToggleMaximizedState();
+        break;
+    }
+
+    event->SetHandled();
+    return;
+  }
+
+  if (event->IsLeftMouseButton() && event->flags() & ui::EF_IS_DOUBLE_CLICK) {
+    click_component_ = HTNOWHERE;
+    if ((target->GetProperty(aura::client::kResizeBehaviorKey) &
+         ui::mojom::kResizeBehaviorCanMaximize) &&
+        previous_click_component == HTCAPTION) {
+      // Our event is a double click in the caption area in a window that can be
+      // maximized. We are responsible for dispatching this as a minimize/
+      // maximize on X11 (Windows converts this to min/max events for us).
+      ToggleMaximizedState();
+      event->SetHandled();
+      return;
+    }
+  }
+
+  MaybeDispatchHostWindowDragMovement(HTCAPTION, event);
+}
+
+void WindowEventFilter::OnClickedMaximizeButton(ui::MouseEvent* event) {
+  aura::Window* target = static_cast<aura::Window*>(event->target());
+  views::Widget* widget = views::Widget::GetWidgetForNativeView(target);
+  if (!widget)
+    return;
+
+  gfx::Rect display_work_area =
+      display::Screen::GetScreen()->GetDisplayNearestWindow(target).work_area();
+  gfx::Rect bounds = widget->GetWindowBoundsInScreen();
+  if (event->IsMiddleMouseButton()) {
+    bounds.set_y(display_work_area.y());
+    bounds.set_height(display_work_area.height());
+    widget->SetBounds(bounds);
+    event->StopPropagation();
+  } else if (event->IsRightMouseButton()) {
+    bounds.set_x(display_work_area.x());
+    bounds.set_width(display_work_area.width());
+    widget->SetBounds(bounds);
+    event->StopPropagation();
+  }
+}
+
+void WindowEventFilter::ToggleMaximizedState() {
+  if (window_tree_host_->IsMaximized())
+    window_tree_host_->Restore();
+  else
+    window_tree_host_->Maximize();
+}
+
+void WindowEventFilter::LowerWindow() {}
+
+void WindowEventFilter::MaybeDispatchHostWindowDragMovement(
+    int hittest,
+    ui::MouseEvent* event) {}
+
+}  // namespace views