Bug 1360278 - Add preference to trigger context menu on mouse up for GTK+ and macOS, r=mstange,smaug

MozReview-Commit-ID: Bg60bD8jIg6

--HG--
extra : rebase_source : cc8bd5796096f49ad4fdab81885a426afd6117e4

modules/libpref/init/all.js

@@ -234,6 +234,10 @@ pref("browser.sessionhistory.max_total_viewers", -1);
 
 pref("ui.use_native_colors", true);
 pref("ui.click_hold_context_menus", false);
+
+// Pop up context menu on mouseup instead of mousedown, if that's the OS default.
+// Note: ignored on Windows (context menus always use mouseup)
+pref("ui.context_menus.after_mouseup", false);
 // Duration of timeout of incremental search in menus (ms).  0 means infinite.
 pref("ui.menu.incremental_search.timeout", 1000);
 // If true, all popups won't hide automatically on blur

widget/cocoa/nsChildView.mm

@@ -4700,8 +4700,10 @@ NSEvent* gLastDragMouseDownEvent = nil;
   if (!mGeckoChild)
     return;
 
-  // Let the superclass do the context menu stuff.
-  [super rightMouseDown:theEvent];
+  if (!nsBaseWidget::ShowContextMenuAfterMouseUp()) {
+    // Let the superclass do the context menu stuff.
+    [super rightMouseDown:theEvent];
+  }
 
   NS_OBJC_END_TRY_ABORT_BLOCK;
 }
@@ -4724,6 +4726,23 @@ NSEvent* gLastDragMouseDownEvent = nil;
 
   nsAutoRetainCocoaObject kungFuDeathGrip(self);
   mGeckoChild->DispatchInputEvent(&geckoEvent);
+  if (!mGeckoChild)
+    return;
+
+  if (nsBaseWidget::ShowContextMenuAfterMouseUp()) {
+    // Let the superclass do the context menu stuff, but pretend it's rightMouseDown.
+    NSEvent *dupeEvent = [NSEvent mouseEventWithType:NSRightMouseDown
+                                            location:theEvent.locationInWindow
+                                       modifierFlags:theEvent.modifierFlags
+                                           timestamp:theEvent.timestamp
+                                        windowNumber:theEvent.windowNumber
+                                             context:theEvent.context
+                                         eventNumber:theEvent.eventNumber
+                                          clickCount:theEvent.clickCount
+                                            pressure:theEvent.pressure];
+
+    [super rightMouseDown:dupeEvent];
+  }
 
   NS_OBJC_END_TRY_ABORT_BLOCK;
 }

widget/gtk/nsWindow.cpp

@@ -2737,6 +2737,19 @@ static guint ButtonMaskFromGDKButton(guint button)
     return GDK_BUTTON1_MASK << (button - 1);
 }
 
+void
+nsWindow::DispatchContextMenuEventFromMouseEvent(uint16_t domButton,
+                                                 GdkEventButton *aEvent)
+{
+    if (domButton == WidgetMouseEvent::eRightButton && MOZ_LIKELY(!mIsDestroyed)) {
+        WidgetMouseEvent contextMenuEvent(true, eContextMenu, this,
+                                          WidgetMouseEvent::eReal);
+        InitButtonEvent(contextMenuEvent, aEvent);
+        contextMenuEvent.pressure = mLastMotionPressure;
+        DispatchInputEvent(&contextMenuEvent);
+    }
+}
+
 void
 nsWindow::OnButtonPressEvent(GdkEventButton *aEvent)
 {
@@ -2806,13 +2819,8 @@ nsWindow::OnButtonPressEvent(GdkEventButton *aEvent)
     DispatchInputEvent(&event);
 
     // right menu click on linux should also pop up a context menu
-    if (domButton == WidgetMouseEvent::eRightButton &&
-        MOZ_LIKELY(!mIsDestroyed)) {
-        WidgetMouseEvent contextMenuEvent(true, eContextMenu, this,
-                                          WidgetMouseEvent::eReal);
-        InitButtonEvent(contextMenuEvent, aEvent);
-        contextMenuEvent.pressure = mLastMotionPressure;
-        DispatchInputEvent(&contextMenuEvent);
+    if (!nsBaseWidget::ShowContextMenuAfterMouseUp()) {
+        DispatchContextMenuEventFromMouseEvent(domButton, aEvent);
     }
 }
 
@@ -2848,6 +2856,11 @@ nsWindow::OnButtonReleaseEvent(GdkEventButton *aEvent)
 
     DispatchInputEvent(&event);
     mLastMotionPressure = pressure;
+
+    // right menu click on linux should also pop up a context menu
+    if (nsBaseWidget::ShowContextMenuAfterMouseUp()) {
+        DispatchContextMenuEventFromMouseEvent(domButton, aEvent);
+    }
 }
 
 void

widget/gtk/nsWindow.h

@@ -245,6 +245,8 @@ private:
 
     void               UpdateClientOffset();
 
+    void               DispatchContextMenuEventFromMouseEvent(uint16_t domButton,
+                                                              GdkEventButton *aEvent);
 public:
     void               ThemeChanged(void);
     void               OnDPIChanged(void);

widget/nsBaseWidget.cpp

@@ -1218,6 +1218,22 @@ nsBaseWidget::DispatchEventToAPZOnly(mozilla::WidgetInputEvent* aEvent)
   }
 }
 
+// static
+bool
+nsBaseWidget::ShowContextMenuAfterMouseUp()
+{
+  static bool gContextMenuAfterMouseUp = false;
+  static bool gContextMenuAfterMouseUpCached = false;
+  if (!gContextMenuAfterMouseUpCached) {
+    Preferences::AddBoolVarCache(&gContextMenuAfterMouseUp,
+                                 "ui.context_menus.after_mouseup",
+                                 false);
+
+    gContextMenuAfterMouseUpCached = true;
+  }
+  return gContextMenuAfterMouseUp;
+}
+
 nsIDocument*
 nsBaseWidget::GetDocument() const
 {

widget/nsBaseWidget.h

@@ -417,6 +417,12 @@ public:
   void RecvScreenPixels(mozilla::ipc::Shmem&& aMem, const ScreenIntSize& aSize) override {};
 #endif
 
+  /**
+   * Whether context menus should only appear on mouseup instead of mousedown,
+   * on OSes where they normally appear on mousedown (macOS, *nix).
+   */
+  static bool ShowContextMenuAfterMouseUp();
+
 protected:
   // These are methods for CompositorWidgetWrapper, and should only be
   // accessed from that class. Derived widgets can choose which methods to