MacViews: Implement Tab Dragging

ui/views/cocoa/bridged_native_widget.h

Index: ui/views/cocoa/bridged_native_widget.h
diff --git a/ui/views/cocoa/bridged_native_widget.h b/ui/views/cocoa/bridged_native_widget.h
index 8f6523042de9eead7500964bd6d0daee8883ae63..76b56f2c9f49dde91691689c6f6e7a5ffc6aed7e 100644
--- a/ui/views/cocoa/bridged_native_widget.h
+++ b/ui/views/cocoa/bridged_native_widget.h
@@ -34,6 +34,7 @@ class BridgedNativeWidgetTestApi;
 }
 
 class CocoaMouseCapture;
+class CocoaWindowMoveLoop;
 class NativeWidgetMac;
 class View;
 
@@ -96,6 +97,11 @@ class VIEWS_EXPORT BridgedNativeWidget
   void ReleaseCapture();
   bool HasCapture();
 
+  // Start moving the window, pinned to the mouse cursor, and monitor events.
+  // Return MOVE_LOOP_SUCCESSFUL on mouse up or MOVE_LOOP_CANCELED on escape.
+  Widget::MoveLoopResult RunMoveLoop(const gfx::Vector2d& drag_offset);
+  void EndMoveLoop();
+
   // See views::Widget.
   void SetNativeWindowProperty(const char* key, void* value);
   void* GetNativeWindowProperty(const char* key) const;
@@ -122,6 +128,10 @@ class VIEWS_EXPORT BridgedNativeWidget
   // Called by the NSWindowDelegate when the size of the window changes.
   void OnSizeChanged();
 
+  // Called once by the NSWindowDelegate when the position of the window has
+  // changed. Called for each mouse event during RunMoveLoop().
+  void OnPositionChanged();
+
   // Called by the NSWindowDelegate when the visibility of the window may have
   // changed. For example, due to a (de)miniaturize operation, or the window
   // being reordered in (or out of) the screen list.
@@ -178,6 +188,7 @@ class VIEWS_EXPORT BridgedNativeWidget
 
  private:
   friend class test::BridgedNativeWidgetTestApi;
+  friend class CocoaWindowMoveLoop;
 
   // Closes all child windows. BridgedNativeWidget children will be destroyed.
   void RemoveOrDestroyChildren();
@@ -253,6 +264,7 @@ class VIEWS_EXPORT BridgedNativeWidget
   base::scoped_nsobject<BridgedContentView> bridged_view_;
   scoped_ptr<ui::InputMethod> input_method_;
   scoped_ptr<CocoaMouseCapture> mouse_capture_;
+  scoped_ptr<CocoaWindowMoveLoop> window_move_loop_;
   scoped_ptr<TooltipManager> tooltip_manager_;
   FocusManager* focus_manager_;  // Weak. Owned by our Widget.
   Widget::InitParams::Type widget_type_;
@@ -269,6 +281,8 @@ class VIEWS_EXPORT BridgedNativeWidget
   // has its own copy, but doesn't provide access to it).
   gfx::Rect bounds_before_fullscreen_;
 
+  base::RunLoop* drag_run_loop_ = nullptr;
+
   // Whether this window wants to be fullscreen. If a fullscreen animation is in
   // progress then it might not be actually fullscreen.
   bool target_fullscreen_state_;