chromeos: fixs easy resize targeter for mash

EasyResizeWindowTargeter only works if a targeter is not installed on the
children of the container. This makes EasyResizeWindowTargeter work by
explicitly checking the parent's WindowTargeter for
SubtreeShouldBeExploredForEvent().

BUG=877099
TEST=covered by test

Change-Id: If5de972623bfbffb87986958010f7c8c51d8b448
Reviewed-on: https://chromium-review.googlesource.com/1187625Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585891}

services/ui/ws2/BUILD.gn

@@ -180,6 +180,7 @@ source_set("tests") {
     "focus_handler_unittest.cc",
     "injected_event_handler_unittest.cc",
     "screen_provider_unittest.cc",
+    "server_window_unittest.cc",
     "user_activity_monitor_unittest.cc",
     "window_delegate_impl_unittest.cc",
     "window_service_observer_unittest.cc",

services/ui/ws2/server_window.cc

@@ -93,6 +93,21 @@ class ServerWindowTargeter : public aura::WindowTargeter {
   ~ServerWindowTargeter() override = default;
 
   // aura::WindowTargeter:
+  bool SubtreeShouldBeExploredForEvent(aura::Window* window,
+                                       const ui::LocatedEvent& event) override {
+    // If the top-level does not have insets, then forward the call to the
+    // parent's WindowTargeter. This is necessary for targeters such as
+    // EasyResizeWindowTargeter to work correctly.
+    if (mouse_extend().IsEmpty() && touch_extend().IsEmpty() &&
+        server_window_->IsTopLevel() && window->parent()) {
+      aura::WindowTargeter* parent_targeter =
+          static_cast<WindowTargeter*>(window->parent()->targeter());
+      if (parent_targeter)
+        return parent_targeter->SubtreeShouldBeExploredForEvent(window, event);
+    }
+    return aura::WindowTargeter::SubtreeShouldBeExploredForEvent(window, event);
+  }
+
   ui::EventTarget* FindTargetForEvent(ui::EventTarget* event_target,
                                       ui::Event* event) override {
     aura::Window* window = static_cast<aura::Window*>(event_target);

services/ui/ws2/server_window_unittest.cc

+// Copyright 2018 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 "services/ui/ws2/server_window.h"
+
+#include <memory>
+
+#include "base/run_loop.h"
+#include "services/ui/ws2/window_service_test_setup.h"
+#include "services/ui/ws2/window_tree.h"
+#include "services/ui/ws2/window_tree_test_helper.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/events/event.h"
+#include "ui/events/event_constants.h"
+#include "ui/wm/core/easy_resize_window_targeter.h"
+
+namespace ui {
+namespace ws2 {
+
+TEST(ServerWindow, FindTargetForWindowWithEasyResizeTargeter) {
+  WindowServiceTestSetup setup;
+  std::unique_ptr<wm::EasyResizeWindowTargeter> easy_resize_window_targeter =
+      std::make_unique<wm::EasyResizeWindowTargeter>(
+          setup.root(), gfx::Insets(-10, -10, -10, -10),
+          gfx::Insets(-10, -10, -10, -10));
+  setup.root()->SetEventTargeter(std::move(easy_resize_window_targeter));
+  aura::Window* top_level =
+      setup.window_tree_test_helper()->NewTopLevelWindow();
+  ASSERT_TRUE(top_level);
+  top_level->SetBounds(gfx::Rect(100, 200, 200, 200));
+  top_level->Show();
+  ui::MouseEvent mouse_event(ui::ET_MOUSE_PRESSED, gfx::Point(105, 195),
+                             gfx::Point(105, 195), base::TimeTicks::Now(),
+                             /* flags */ 0,
+                             /* changed_button_flags_ */ 0);
+
+  // Even though the mouse is not over |top_level| it should be returned as the
+  // target because EasyResizeWindowTargeter enlarges the hit area.
+  EXPECT_EQ(top_level, setup.root()->targeter()->FindTargetForEvent(
+                           setup.root(), &mouse_event));
+
+  // Repeat with a location outside the extended hit region and ensure
+  // |top_level| is not returned.
+  ui::MouseEvent mouse_event2(ui::ET_MOUSE_PRESSED, gfx::Point(5, 5),
+                              gfx::Point(5, 5), base::TimeTicks::Now(),
+                              /* flags */ 0,
+                              /* changed_button_flags_ */ 0);
+  EXPECT_NE(top_level, setup.root()->targeter()->FindTargetForEvent(
+                           setup.root(), &mouse_event2));
+}
+
+}  // namespace ws2
+}  // namespace ui

ui/aura/window.h

@@ -216,6 +216,7 @@ class AURA_EXPORT Window : public ui::LayerDelegate,
   // event-targeter.
   std::unique_ptr<ui::EventTargeter> SetEventTargeter(
       std::unique_ptr<ui::EventTargeter> targeter);
+  ui::EventTargeter* targeter() { return targeter_.get(); }
 
   // Changes the bounds of the window. If present, the window's parent's
   // LayoutManager may adjust the bounds.