Explicitly suppress scrolling for wheel events that will trigger zooming

We added a flag in Blink to decide if Ctrl-wheel-scroll should scroll or zoom, and now we use this flag in chromium code.

This patch is part of a series:

patch #1: https://codereview.chromium.org/759073002
patch #2: This CL
patch #3: https://codereview.chromium.org/768443002

BUG=397027, 378755

Review URL: https://codereview.chromium.org/739013008

Cr-Commit-Position: refs/heads/master@{#309472}

2 files changed, 5 insertions, 5 deletions

diff --git a/content/renderer/input/input_handler_proxy.cc b/content/renderer/input/input_handler_proxy.cc
index 3edb957..602f113 100644
--- a/content/renderer/input/input_handler_proxy.cc
+++ b/content/renderer/input/input_handler_proxy.cc
@@ -324,9 +324,9 @@ InputHandlerProxy::EventDisposition InputHandlerProxy::HandleMouseWheel(
     // TODO(jamesr): We don't properly handle scroll by page in the compositor
     // thread, so punt it to the main thread. http://crbug.com/236639
     result = DID_NOT_HANDLE;
-  } else if (wheel_event.modifiers & WebInputEvent::ControlKey) {
-    // Wheel events involving the control key never trigger scrolling, only
-    // event handlers.  Forward to the main thread.
+  } else if (!wheel_event.canScroll) {
+    // Wheel events with |canScroll| == false will not trigger scrolling,
+    // only event handlers.  Forward to the main thread.
     result = DID_NOT_HANDLE;
   } else if (smooth_scroll_enabled_) {
     cc::InputHandler::ScrollStatus scroll_status =
diff --git a/content/renderer/input/input_handler_proxy_unittest.cc b/content/renderer/input/input_handler_proxy_unittest.cc
index cb85701..ad715ac 100644
--- a/content/renderer/input/input_handler_proxy_unittest.cc
+++ b/content/renderer/input/input_handler_proxy_unittest.cc
@@ -288,12 +288,12 @@ TEST_F(InputHandlerProxyTest, MouseWheelByPageMainThread) {
   testing::Mock::VerifyAndClearExpectations(&mock_client_);
 }
 
-TEST_F(InputHandlerProxyTest, MouseWheelWithCtrl) {
+TEST_F(InputHandlerProxyTest, MouseWheelWithCtrlNotScroll) {
   expected_disposition_ = InputHandlerProxy::DID_NOT_HANDLE;
   WebMouseWheelEvent wheel;
   wheel.type = WebInputEvent::MouseWheel;
   wheel.modifiers = WebInputEvent::ControlKey;
-
+  wheel.canScroll = false;
   EXPECT_EQ(expected_disposition_, input_handler_->HandleInputEvent(wheel));
   testing::Mock::VerifyAndClearExpectations(&mock_client_);
 }