aura: Add an EasyResizeWindowTargeter.

ui/wm/public/easy_resize_window_targeter.h

Index: ui/wm/public/easy_resize_window_targeter.h
diff --git a/ui/wm/public/easy_resize_window_targeter.h b/ui/wm/public/easy_resize_window_targeter.h
new file mode 100644
index 0000000000000000000000000000000000000000..c4c7137abd3808680334f256bb724f21442340b3
--- /dev/null
+++ b/ui/wm/public/easy_resize_window_targeter.h
@@ -0,0 +1,48 @@
+// Copyright 2014 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.
+
+#ifndef UI_WM_PUBLIC_EASY_RESIZE_WINDOW_TARGETER_H_
+#define UI_WM_PUBLIC_EASY_RESIZE_WINDOW_TARGETER_H_
+
+#include "ui/aura/window_targeter.h"
+#include "ui/gfx/geometry/insets.h"
+
+namespace wm {
+
+// An EventTargeter for a container window that uses a slightly larger
+// hit-target region for easier resize.
+class EasyResizeWindowTargeter : public aura::WindowTargeter {
+ public:
+  // |container| window is the owner of this targeter.
+  EasyResizeWindowTargeter(aura::Window* container,
+                           const gfx::Insets& mouse_extend,
+                           const gfx::Insets& touch_extend);
+
+  virtual ~EasyResizeWindowTargeter();
+
+ protected:
+  void set_mouse_extend(const gfx::Insets& mouse_extend) {
+    mouse_extend_ = mouse_extend;
+  }
+
+  void set_touch_extend(const gfx::Insets& touch_extend) {
+    touch_extend_ = touch_extend;
+  }
+
+  // aura::WindowTargeter:
+  virtual bool EventLocationInsideBounds(
+      aura::Window* window,
+      const ui::LocatedEvent& event) const OVERRIDE;
+
+ private:
+  aura::Window* container_;
+  gfx::Insets mouse_extend_;
+  gfx::Insets touch_extend_;
+
+  DISALLOW_COPY_AND_ASSIGN(EasyResizeWindowTargeter);
+};
+
+}  // namespace wm
+
+#endif  // UI_WM_PUBLIC_EASY_RESIZE_WINDOW_TARGETER_H_