Route OnDragEvent through ViewAndroid tree

ui/android/view_android.h

 // Copyright 2013 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_ANDROID_VIEW_ANDROID_H_
 #define UI_ANDROID_VIEW_ANDROID_H_
 
 #include <list>
 
 #include "base/android/jni_weak_ref.h"
 #include "base/bind.h"
 #include "base/memory/ref_counted.h"
 #include "ui/android/ui_android_export.h"
 #include "ui/gfx/geometry/rect_f.h"
 
 namespace cc {
 class Layer;
 }
 
 namespace ui {
+class DragEventAndroid;
 class EventForwarder;
 class MotionEventAndroid;
 class ViewClient;
 class WindowAndroid;
 
 // A simple container for a UI layer.
 // At the root of the hierarchy is a WindowAndroid, when attached.
 // Dispatches input/view events coming from Java layer. Hit testing against
 // those events is implemented so that the |ViewClient| will be invoked
 // when the event got hit on the area defined by |layout_params_|.
@@ skipping 25 matching lines @@
     // TODO(jinsukkim): Following weak refs can be cast to strong refs which
     //     cannot be garbage-collected and leak memory. Rewrite not to use them.
     //     see comments in crrev.com/2103243002.
     JavaObjectWeakGlobalRef view_;
     JavaObjectWeakGlobalRef delegate_;
 
     // Default copy/assign disabled by move constructor.
   };
 
   // Layout parameters used to set the view's position and size.
-  // Position is in parent's coordinate space.
+  // Position is in parent's coordinate space, and all the values
+  // are in CSS pixel.
   struct LayoutParams {
     static LayoutParams MatchParent() { return {true, 0, 0, 0, 0}; }
     static LayoutParams Normal(int x, int y, int width, int height) {
       return {false, x, y, width, height};
     };
 
     bool match_parent;  // Bounds matches that of the parent if true.
     int x;
     int y;
     int width;
@@ skipping 74 matching lines @@
 
   float GetDipScale();
 
  protected:
   ViewAndroid* parent_;
 
  private:
   friend class EventForwarder;
   friend class ViewAndroidBoundsTest;
 
-  using ViewClientCallback =
-      const base::Callback<bool(ViewClient*, const MotionEventAndroid&)>;
-
+  bool OnDragEvent(const DragEventAndroid& event);
   bool OnTouchEvent(const MotionEventAndroid& event, bool for_touch_handle);
   bool OnMouseEvent(const MotionEventAndroid& event);
   bool OnMouseWheelEvent(const MotionEventAndroid& event);
 
   void RemoveChild(ViewAndroid* child);
 
-  bool HitTest(ViewClientCallback send_to_client,
-               const MotionEventAndroid& event);
+  template <typename E>
+  using ViewClientCallback =
+      const base::Callback<bool(ViewClient*, const E&, const gfx::PointF&)>;
 
+  template <typename E>
+  bool HitTest(ViewClientCallback<E> send_to_client,
+               const E& event,
+               const gfx::PointF& point);
+
+  static bool SendDragEventToClient(ViewClient* client,
+                                    const DragEventAndroid& event,
+                                    const gfx::PointF& point);
   static bool SendTouchEventToClient(bool for_touch_handle,
                                      ViewClient* client,
-                                     const MotionEventAndroid& event);
+                                     const MotionEventAndroid& event,
+                                     const gfx::PointF& point);
   static bool SendMouseEventToClient(ViewClient* client,
-                                     const MotionEventAndroid& event);
+                                     const MotionEventAndroid& event,
+                                     const gfx::PointF& point);
   static bool SendMouseWheelEventToClient(ViewClient* client,
-                                          const MotionEventAndroid& event);
+                                          const MotionEventAndroid& event,
+                                          const gfx::PointF& point);
 
   bool has_event_forwarder() const { return !!event_forwarder_; }
 
   // Checks if there is any event forwarder in any node up to root.
   static bool RootPathHasEventForwarder(ViewAndroid* view);
 
   // Checks if there is any event forwarder in the node paths down to
   // each leaf of subtree.
   static bool SubtreeHasEventForwarder(ViewAndroid* view);
 
@@ skipping 17 matching lines @@
 
   gfx::Vector2dF content_offset_;  // in CSS pixel.
   std::unique_ptr<EventForwarder> event_forwarder_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewAndroid);
 };
 
 }  // namespace ui
 
 #endif  // UI_ANDROID_VIEW_ANDROID_H_