Start sending auxclick instead of click for non-primary buttons

third_party/WebKit/Source/core/input/EventHandler.cpp

Index: third_party/WebKit/Source/core/input/EventHandler.cpp
diff --git a/third_party/WebKit/Source/core/input/EventHandler.cpp b/third_party/WebKit/Source/core/input/EventHandler.cpp
index 0d12edaba07fdd4422f52c88d0470b388c743200..69ea301be75d9697b8bbe72cc4ef1c08d61ded12 100644
--- a/third_party/WebKit/Source/core/input/EventHandler.cpp
+++ b/third_party/WebKit/Source/core/input/EventHandler.cpp
@@ -1150,16 +1150,18 @@ WebInputEventResult EventHandler::handleMouseReleaseEvent(const PlatformMouseEve
 
     WebInputEventResult eventResult = updatePointerTargetAndDispatchEvents(EventTypeNames::mouseup, mev.innerNode(), m_clickCount, mev.event());
 
-    bool contextMenuEvent = mouseEvent.button() == RightButton;
+    // We only prevent click event when the click may cause contextmenu to popup.
+    // However, we always send auxclick.
+    bool macContextMenuEvent = false;

[bokan, 2016/08/12 15:29:17]

Is this a change in behaviour? It looks like we'd previously prevent sending the
click event on right clicks and now we send it.

[Navid Zolghadr, 2016/08/12 15:39:16]

That is correct. But not quite a change in the behavior. We were preventing
click event on right click (and left click when happens with control on Mac).
Now we send auxclick for right clicks. So we don't prevent that and we send
auxclick if right click happens.

[bokan, 2016/08/12 15:42:20]

Got it. But if RuntimeEnabledFeatures::auxclickEnabled is off, won't we now send
a click event?

[Navid Zolghadr, 2016/08/12 16:01:18]

Right. Thanks for the catch. I'm surprised why the output of the test in stable
didn't break in that case. Probably context menu opens and consumes the events
or something like that. But I fixed this contextMenuEvent to consider whether
auxclick is enabled or not and initialized it based on that.

 #if OS(MACOSX)
     // FIXME: The Mac port achieves the same behavior by checking whether the context menu is currently open in WebPage::mouseEvent(). Consider merging the implementations.
     if (mouseEvent.button() == LeftButton && mouseEvent.getModifiers() & PlatformEvent::CtrlKey)
-        contextMenuEvent = true;
+        macContextMenuEvent = true;
 #endif
 
     WebInputEventResult clickEventResult = WebInputEventResult::NotHandled;
     const bool shouldDispatchClickEvent = m_clickCount > 0
-        && !contextMenuEvent
+        && !macContextMenuEvent
         && mev.innerNode() && m_clickNode
         && mev.innerNode()->canParticipateInFlatTree() && m_clickNode->canParticipateInFlatTree()
         && !(selectionController().hasExtendedSelection() && isLinkSelection(mev));
@@ -1183,7 +1185,10 @@ WebInputEventResult EventHandler::handleMouseReleaseEvent(const PlatformMouseEve
             // correctly. Moreover, clickTargetNode is different from
             // mev.innerNode at drag-release.
             clickEventResult = toWebInputEventResult(clickTargetNode->dispatchMouseEvent(mev.event(),
-                EventTypeNames::click, m_clickCount));
+                !RuntimeEnabledFeatures::auxclickEnabled() || (mev.event().button() == MouseButton::LeftButton)
+                    ? EventTypeNames::click
+                    : EventTypeNames::auxclick,
+                m_clickCount));
         }
     }