Emit scroll-touch-edge event instead of changing the behavior of scroll-touch-begin/end

fix #6873

atom/browser/api/atom_api_window.cc

@@ -230,6 +230,10 @@ void Window::OnWindowScrollTouchEnd() {
   Emit("scroll-touch-end");
 }
 
+void Window::OnWindowScrollTouchEdge() {
+  Emit("scroll-touch-edge");
+}
+
 void Window::OnWindowSwipe(const std::string& direction) {
   Emit("swipe", direction);
 }

atom/browser/api/atom_api_window.h

@@ -74,6 +74,7 @@ class Window : public mate::TrackableObject<Window>,
   void OnWindowMoved() override;
   void OnWindowScrollTouchBegin() override;
   void OnWindowScrollTouchEnd() override;
+  void OnWindowScrollTouchEdge() override;
   void OnWindowSwipe(const std::string& direction) override;
   void OnWindowEnterFullScreen() override;
   void OnWindowLeaveFullScreen() override;

atom/browser/native_window.cc

@@ -504,6 +504,11 @@ void NativeWindow::NotifyWindowScrollTouchEnd() {
                     OnWindowScrollTouchEnd());
 }
 
+void NativeWindow::NotifyWindowScrollTouchEdge() {
+  FOR_EACH_OBSERVER(NativeWindowObserver, observers_,
+                    OnWindowScrollTouchEdge());
+}
+
 void NativeWindow::NotifyWindowSwipe(const std::string& direction) {
   FOR_EACH_OBSERVER(NativeWindowObserver, observers_,
                     OnWindowSwipe(direction));

atom/browser/native_window.h

@@ -207,6 +207,7 @@ class NativeWindow : public base::SupportsUserData,
   void NotifyWindowMoved();
   void NotifyWindowScrollTouchBegin();
   void NotifyWindowScrollTouchEnd();
+  void NotifyWindowScrollTouchEdge();
   void NotifyWindowSwipe(const std::string& direction);
   void NotifyWindowEnterFullScreen();
   void NotifyWindowLeaveFullScreen();

atom/browser/native_window_mac.h

@@ -160,9 +160,6 @@ class NativeWindowMac : public NativeWindow,
   // The "titleBarStyle" option.
   TitleBarStyle title_bar_style_;
 
-  // Whether user has scrolled the page to edge.
-  bool is_edge_;
-
   DISALLOW_COPY_AND_ASSIGN(NativeWindowMac);
 };
 

atom/browser/native_window_mac.mm

@@ -530,8 +530,7 @@ NativeWindowMac::NativeWindowMac(
     : NativeWindow(web_contents, options, parent),
       is_kiosk_(false),
       attention_request_id_(0),
-      title_bar_style_(NORMAL),
-      is_edge_(false) {
+      title_bar_style_(NORMAL) {
   int width = 800, height = 600;
   options.Get(options::kWidth, &width);
   options.Get(options::kHeight, &height);
@@ -676,16 +675,14 @@ NativeWindowMac::NativeWindowMac(
       if (!web_contents)
         return event;
 
-      if (!began && is_edge_ && (([event phase] == NSEventPhaseMayBegin) ||
+      if (!began && (([event phase] == NSEventPhaseMayBegin) ||
                                  ([event phase] == NSEventPhaseBegan))) {
         this->NotifyWindowScrollTouchBegin();
         began = YES;
-        is_edge_ = false;
       } else if (began && (([event phase] == NSEventPhaseEnded) ||
                            ([event phase] == NSEventPhaseCancelled))) {
         this->NotifyWindowScrollTouchEnd();
         began = NO;
-        is_edge_ = false;
       }
       return event;
   }];
@@ -1131,7 +1128,7 @@ void NativeWindowMac::OnInputEvent(const blink::WebInputEvent& event) {
     case blink::WebInputEvent::GestureScrollBegin:
     case blink::WebInputEvent::GestureScrollUpdate:
     case blink::WebInputEvent::GestureScrollEnd:
-      is_edge_ = true;
+        this->NotifyWindowScrollTouchEdge();
       break;
     default:
       break;

atom/browser/native_window_observer.h

@@ -64,6 +64,7 @@ class NativeWindowObserver {
   virtual void OnWindowMoved() {}
   virtual void OnWindowScrollTouchBegin() {}
   virtual void OnWindowScrollTouchEnd() {}
+  virtual void OnWindowScrollTouchEdge() {}
   virtual void OnWindowSwipe(const std::string& direction) {}
   virtual void OnWindowEnterFullScreen() {}
   virtual void OnWindowLeaveFullScreen() {}

docs/api/browser-window.md

@@ -448,6 +448,10 @@ Emitted when scroll wheel event phase has begun.
 
 Emitted when scroll wheel event phase has ended.
 
+#### Event: 'scroll-touch-edge' _macOS_
+
+Emitted when scroll wheel event phase filed upon reaching the edge of element.
+
 #### Event: 'swipe' _macOS_
 
 Returns: