Send the WebMouseWheelEvents unconverted if Shift is down.

ui/events/blink/web_input_event.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/events/blink/web_input_event.h"
 
 #include "ui/events/base_event_utils.h"
 #include "ui/events/blink/blink_event_util.h"
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
@@ skipping 118 matching lines @@
 blink::WebMouseWheelEvent MakeWebMouseWheelEventFromUiEvent(
     const ScrollEvent& event) {
   blink::WebMouseWheelEvent webkit_event;
 
   webkit_event.type = blink::WebInputEvent::MouseWheel;
   webkit_event.button = blink::WebMouseEvent::Button::NoButton;
   webkit_event.modifiers = EventFlagsToWebEventModifiers(event.flags());
   webkit_event.timeStampSeconds = EventTimeStampToSeconds(event.time_stamp());
   webkit_event.hasPreciseScrollingDeltas = true;
 
-  float offset_ordinal_x = 0.f;
-  float offset_ordinal_y = 0.f;
-  if ((event.flags() & EF_SHIFT_DOWN) != 0 && event.x_offset() == 0) {
-    webkit_event.deltaX = event.y_offset();
-    webkit_event.deltaY = 0;
-    offset_ordinal_x = event.y_offset_ordinal();
-    offset_ordinal_y = event.x_offset_ordinal();
-  } else {
-    webkit_event.deltaX = event.x_offset();
-    webkit_event.deltaY = event.y_offset();
-    offset_ordinal_x = event.x_offset_ordinal();
-    offset_ordinal_y = event.y_offset_ordinal();
-  }
+  float offset_ordinal_x = event.x_offset_ordinal();
+  float offset_ordinal_y = event.y_offset_ordinal();
+  webkit_event.deltaX = event.x_offset();
+  webkit_event.deltaY = event.y_offset();
 
   if (offset_ordinal_x != 0.f && webkit_event.deltaX != 0.f)
     webkit_event.accelerationRatioX = offset_ordinal_x / webkit_event.deltaX;
   webkit_event.wheelTicksX = webkit_event.deltaX / MouseWheelEvent::kWheelDelta;
   webkit_event.wheelTicksY = webkit_event.deltaY / MouseWheelEvent::kWheelDelta;
   if (offset_ordinal_y != 0.f && webkit_event.deltaY != 0.f)
     webkit_event.accelerationRatioY = offset_ordinal_y / webkit_event.deltaY;
 
   webkit_event.pointerType =
       EventPointerTypeToWebPointerType(event.pointer_details().pointer_type);
@@ skipping 268 matching lines @@
 
 blink::WebMouseWheelEvent MakeWebMouseWheelEventFromUiEvent(
     const MouseWheelEvent& event) {
   blink::WebMouseWheelEvent webkit_event;
 
   webkit_event.type = blink::WebInputEvent::MouseWheel;
   webkit_event.button = blink::WebMouseEvent::Button::NoButton;
   webkit_event.modifiers = EventFlagsToWebEventModifiers(event.flags());
   webkit_event.timeStampSeconds = EventTimeStampToSeconds(event.time_stamp());
 
-  if ((event.flags() & EF_SHIFT_DOWN) != 0 && event.x_offset() == 0) {
-    webkit_event.deltaX = event.y_offset();
-    webkit_event.deltaY = 0;
-  } else {
-    webkit_event.deltaX = event.x_offset();
-    webkit_event.deltaY = event.y_offset();
-  }
+  webkit_event.deltaX = event.x_offset();
+  webkit_event.deltaY = event.y_offset();
 
   webkit_event.wheelTicksX = webkit_event.deltaX / MouseWheelEvent::kWheelDelta;
   webkit_event.wheelTicksY = webkit_event.deltaY / MouseWheelEvent::kWheelDelta;
 
   webkit_event.tiltX = roundf(event.pointer_details().tilt_x);
   webkit_event.tiltY = roundf(event.pointer_details().tilt_y);
   webkit_event.force = event.pointer_details().force;
   webkit_event.pointerType =
       EventPointerTypeToWebPointerType(event.pointer_details().pointer_type);
 
   return webkit_event;
 }
 
 }  // namespace ui