Make ServerWindow responsible for interior resize handle event routing.

Bug: 883072
Change-Id: I24380dc595a7446e463422848916b73845945861
Reviewed-on: https://chromium-review.googlesource.com/1227357Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Evan Stade <estade@chromium.org>
Cr-Commit-Position: refs/heads/master@{#592943}

services/ws/server_window.cc

@@ -10,7 +10,9 @@
 #include "components/viz/host/host_frame_sink_manager.h"
 #include "services/ws/drag_drop_delegate.h"
 #include "services/ws/embedding.h"
+#include "services/ws/public/mojom/window_tree_constants.mojom.h"
 #include "services/ws/window_tree.h"
+#include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/capture_client_observer.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window.h"
@@ -36,10 +38,22 @@ bool IsLocationInNonClientArea(const aura::Window* window,
   if (!server_window || !server_window->IsTopLevel())
     return false;
 
-  // Locations outside the bounds, assume it's in extended hit test area, which
-  // is non-client area.
-  if (!gfx::Rect(window->bounds().size()).Contains(location))
-    return true;
+  // Locations inside bounds but within the resize insets count as non-client
+  // area. Locations outside the bounds, assume it's in extended hit test area,
+  // which is non-client area.
+  ui::WindowShowState window_state =
+      window->GetProperty(aura::client::kShowStateKey);
+  if ((window->GetProperty(aura::client::kResizeBehaviorKey) &
+       ws::mojom::kResizeBehaviorCanResize) &&
+      (window_state != ui::WindowShowState::SHOW_STATE_MAXIMIZED) &&
+      (window_state != ui::WindowShowState::SHOW_STATE_FULLSCREEN)) {
+    int resize_handle_size =
+        window->GetProperty(aura::client::kResizeHandleInset);
+    gfx::Rect non_handle_area(window->bounds().size());
+    non_handle_area.Inset(gfx::Insets(resize_handle_size));
+    if (!non_handle_area.Contains(location))
+      return true;
+  }
 
   gfx::Rect client_area(window->bounds().size());
   client_area.Inset(server_window->client_area());

services/ws/server_window_unittest.cc

@@ -11,6 +11,7 @@
 #include "services/ws/window_tree.h"
 #include "services/ws/window_tree_test_helper.h"
 #include "testing/gtest/include/gtest/gtest.h"
+#include "ui/aura/client/aura_constants.h"
 #include "ui/events/event.h"
 #include "ui/events/event_constants.h"
 #include "ui/wm/core/easy_resize_window_targeter.h"
@@ -48,4 +49,42 @@ TEST(ServerWindow, FindTargetForWindowWithEasyResizeTargeter) {
                            setup.root(), &mouse_event2));
 }
 
+TEST(ServerWindow, FindTargetForWindowWithResizeInset) {
+  WindowServiceTestSetup setup;
+
+  aura::Window* top_level =
+      setup.window_tree_test_helper()->NewTopLevelWindow();
+  ASSERT_TRUE(top_level);
+  const gfx::Rect top_level_bounds(100, 200, 200, 200);
+  top_level->SetBounds(top_level_bounds);
+  top_level->Show();
+
+  aura::Window* child_window = setup.window_tree_test_helper()->NewWindow();
+  ASSERT_TRUE(child_window);
+  top_level->AddChild(child_window);
+  child_window->SetBounds(gfx::Rect(top_level_bounds.size()));
+  child_window->Show();
+
+  const int kInset = 4;
+  // Target an event at the resize inset area.
+  gfx::Point click_point =
+      top_level_bounds.left_center() + gfx::Vector2d(kInset / 2, 0);
+  // With no resize inset set yet, the event should go to the child window.
+  ui::MouseEvent mouse_event(ui::ET_MOUSE_PRESSED, click_point, click_point,
+                             base::TimeTicks::Now(),
+                             /* flags */ 0,
+                             /* changed_button_flags_ */ 0);
+  EXPECT_EQ(child_window, setup.root()->targeter()->FindTargetForEvent(
+                              setup.root(), &mouse_event));
+
+  // With the resize inset, the event should go to the toplevel.
+  top_level->SetProperty(aura::client::kResizeHandleInset, kInset);
+  ui::MouseEvent mouse_event_2(ui::ET_MOUSE_PRESSED, click_point, click_point,
+                               base::TimeTicks::Now(),
+                               /* flags */ 0,
+                               /* changed_button_flags_ */ 0);
+  EXPECT_EQ(top_level, setup.root()->targeter()->FindTargetForEvent(
+                           setup.root(), &mouse_event_2));
+}
+
 }  // namespace ws

ui/aura/client/aura_constants.cc

@@ -68,6 +68,7 @@ DEFINE_UI_CLASS_PROPERTY_KEY(
 DEFINE_UI_CLASS_PROPERTY_KEY(int32_t,
                              kResizeBehaviorKey,
                              ws::mojom::kResizeBehaviorCanResize);
+DEFINE_UI_CLASS_PROPERTY_KEY(int, kResizeHandleInset, 0);
 DEFINE_OWNED_UI_CLASS_PROPERTY_KEY(gfx::Rect, kRestoreBoundsKey, nullptr);
 DEFINE_UI_CLASS_PROPERTY_KEY(
     ui::WindowShowState, kShowStateKey, ui::SHOW_STATE_DEFAULT);

ui/aura/client/aura_constants.h

@@ -124,6 +124,12 @@ AURA_EXPORT extern const WindowProperty<ui::WindowShowState>* const
 // ws::mojom::kResizeBehavior values.
 AURA_EXPORT extern const WindowProperty<int32_t>* const kResizeBehaviorKey;
 
+// Reserves a number of dip around the window (i.e. inset from its exterior
+// border) for event routing back to the top level window. This is used for
+// routing events to toplevel window resize handles. It should only be respected
+// for restored windows (maximized and fullscreen can't be drag-resized).
+AURA_EXPORT extern const WindowProperty<int>* const kResizeHandleInset;
+
 // A property key to store the restore bounds in screen coordinates for a
 // window.
 AURA_EXPORT extern const WindowProperty<gfx::Rect*>* const kRestoreBoundsKey;