Explicitly suppress scrolling for wheel events that will trigger zooming

content/common/input/synthetic_web_input_event_builders.cc

 // Copyright 2013 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 "content/common/input/synthetic_web_input_event_builders.h"
 
 #include "base/logging.h"
 #include "content/common/input/web_touch_event_traits.h"
 #include "ui/events/keycodes/keyboard_codes.h"
 
@@ skipping 50 matching lines @@
   WebMouseWheelEvent result;
   result.type = WebInputEvent::MouseWheel;
   result.deltaX = dx;
   result.deltaY = dy;
   if (dx)
     result.wheelTicksX = dx > 0.0f ? 1.0f : -1.0f;
   if (dy)
     result.wheelTicksY = dy > 0.0f ? 1.0f : -1.0f;
   result.modifiers = modifiers;
   result.hasPreciseScrollingDeltas = precise;
+  result.canScroll = true;
   return result;
 }
 
 WebKeyboardEvent SyntheticWebKeyboardEventBuilder::Build(
     WebInputEvent::Type type) {
   DCHECK(WebInputEvent::isKeyboardEventType(type));
   WebKeyboardEvent result;
   result.type = type;
   result.windowsKeyCode = ui::VKEY_L;  // non-null made up value.
   return result;
@@ skipping 129 matching lines @@
   touches[index].state = WebTouchPoint::StateCancelled;
   WebTouchEventTraits::ResetType(
       WebInputEvent::TouchCancel, timeStampSeconds, this);
 }
 
 void SyntheticWebTouchEvent::SetTimestamp(base::TimeDelta timestamp) {
   timeStampSeconds = timestamp.InSecondsF();
 }
 
 }  // namespace content