Fix frame coordinate translation issue with scroll views.

third_party/WebKit/Source/web/WebPluginContainerImpl.cpp

Index: third_party/WebKit/Source/web/WebPluginContainerImpl.cpp
diff --git a/third_party/WebKit/Source/web/WebPluginContainerImpl.cpp b/third_party/WebKit/Source/web/WebPluginContainerImpl.cpp
index 7802cd487bbc30deeef86de85c1bef7fb4cb9b58..04138dd602db31c35c883e04d8729e8f55785fc4 100644
--- a/third_party/WebKit/Source/web/WebPluginContainerImpl.cpp
+++ b/third_party/WebKit/Source/web/WebPluginContainerImpl.cpp
@@ -710,6 +710,8 @@ void WebPluginContainerImpl::HandleMouseEvent(MouseEvent* event) {
   // in the call to HandleEvent. See http://b/issue?id=1362948
   FrameView* parent_view = ToFrameView(Parent());
 
+  // TODO(dtapuska): Move WebMouseEventBuilder into the anonymous namespace
+  // in this class.
   WebMouseEventBuilder transformed_event(
       ToFrameView(Parent()), LayoutItem(element_->GetLayoutObject()), *event);
   if (transformed_event.GetType() == WebInputEvent::kUndefined)
@@ -767,6 +769,14 @@ void WebPluginContainerImpl::HandleDragEvent(MouseEvent* event) {
 void WebPluginContainerImpl::HandleWheelEvent(WheelEvent* event) {
   WebFloatPoint absolute_root_frame_location =

[bokan, 2017/04/12 17:28:44]

This (and below) should now be called absolute_location or content_location,
right?

[dtapuska, 2017/04/12 19:02:56]

Done.

       event->NativeEvent().PositionInRootFrame();
+
+  FrameView* view = ToFrameView(Parent());
+  // Translate the root frame position to content coordinates.
+  if (view) {
+    absolute_root_frame_location =
+        view->RootFrameToContents(absolute_root_frame_location);
+  }
+
   IntPoint local_point =
       RoundedIntPoint(element_->GetLayoutObject()->AbsoluteToLocal(
           absolute_root_frame_location, kUseTransforms));
@@ -830,9 +840,18 @@ void WebPluginContainerImpl::HandleTouchEvent(TouchEvent* event) {
       WebTouchEvent transformed_event =
           event->NativeEvent()->FlattenTransform();
 
+      FrameView* view = ToFrameView(Parent());
+
       for (unsigned i = 0; i < transformed_event.touches_length; ++i) {
         WebFloatPoint absolute_root_frame_location =
             transformed_event.touches[i].position;
+
+        // Translate the root frame position to content coordinates.
+        if (view) {
+          absolute_root_frame_location =
+              view->RootFrameToContents(absolute_root_frame_location);
+        }
+
         IntPoint local_point =
             RoundedIntPoint(element_->GetLayoutObject()->AbsoluteToLocal(
                 absolute_root_frame_location, kUseTransforms));