Explicitly suppress scrolling for wheel events that will trigger zooming

content/browser/renderer_host/render_widget_host_view_aura_unittest.cc

 // Copyright (c) 2012 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/browser/renderer_host/render_widget_host_view_aura.h"
 
 #include "base/basictypes.h"
 #include "base/command_line.h"
 #include "base/memory/shared_memory.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 290 matching lines @@
  private:
   aura::Window* owner_;
   DISALLOW_COPY_AND_ASSIGN(FullscreenLayoutManager);
 };
 
 class MockWindowObserver : public aura::WindowObserver {
  public:
   MOCK_METHOD2(OnDelegatedFrameDamage, void(aura::Window*, const gfx::Rect&));
 };
 
+const WebInputEvent* GetInputEventFromMessage(const IPC::Message& message) {
+  PickleIterator iter(message);
+  const char* data;
+  int data_length;
+  if (!message.ReadData(&iter, &data, &data_length))
+    return NULL;
+  return reinterpret_cast<const WebInputEvent*>(data);
+}
+
 }  // namespace
 
 class RenderWidgetHostViewAuraTest : public testing::Test {
  public:
   RenderWidgetHostViewAuraTest()
       : widget_host_uses_shutdown_to_destroy_(false),
         is_guest_view_hack_(false),
         browser_thread_for_ui_(BrowserThread::UI, &message_loop_) {}
 
   void SetUpEnvironment() {
@@ skipping 2672 matching lines @@
 
   const NativeWebKeyboardEvent* event = delegate_.last_event();
   EXPECT_NE(nullptr, event);
   if (event) {
     EXPECT_EQ(key_event.key_code(), event->windowsKeyCode);
     EXPECT_EQ(ui::KeycodeConverter::DomCodeToNativeKeycode(key_event.code()),
               event->nativeKeyCode);
   }
 }
 
+TEST_F(RenderWidgetHostViewAuraTest, SetCanScrollForWebMouseWheelEvent) {
+  view_->InitAsChild(NULL);
+  view_->Show();
+
+  sink_->ClearMessages();
+
+  // Simulates the mouse wheel event.
+  ui::MouseWheelEvent event(gfx::Vector2d(1, 1),
+                             gfx::Point(), gfx::Point(),
+                             ui::EF_CONTROL_DOWN, 0);
+  view_->OnMouseEvent(&event);
+
+  const WebInputEvent* input_event =
+      GetInputEventFromMessage(*sink_->GetMessageAt(0));
+  const WebMouseWheelEvent* wheel_event =
+      static_cast<const WebMouseWheelEvent*>(input_event);
+  // Check if the canScroll set to false when ctrl-scroll is generated from
+  // mouse wheel event.
+  EXPECT_FALSE(wheel_event->canScroll);

[Rick Byers, 2014/12/18 15:18:14]

Great, this is the key case you want to test.  But you should also verify that
you get TRUE when modifiers doesn't have CONTROL, and when it does but you have
precise deltas.  Then you will have tested all the important cases.

[lanwei, 2014/12/19 02:55:44]

Done.

+}
+
 }  // namespace content