Add blink::WebInputEvent::IsPinchGestureEventType().

extensions/browser/app_window/app_web_contents_helper.cc

Index: extensions/browser/app_window/app_web_contents_helper.cc
diff --git a/extensions/browser/app_window/app_web_contents_helper.cc b/extensions/browser/app_window/app_web_contents_helper.cc
index f8077bbe9d646c2e33e2644a1b020e2630be9fb9..2bd902e5aab274514d3fe8b8eb50ba13a26a5f16 100644
--- a/extensions/browser/app_window/app_web_contents_helper.cc
+++ b/extensions/browser/app_window/app_web_contents_helper.cc
@@ -33,9 +33,7 @@ AppWebContentsHelper::AppWebContentsHelper(
 bool AppWebContentsHelper::ShouldSuppressGestureEvent(
     const blink::WebGestureEvent& event) {
   // Disable pinch zooming in app windows.
-  return event.GetType() == blink::WebGestureEvent::kGesturePinchBegin ||
-         event.GetType() == blink::WebGestureEvent::kGesturePinchUpdate ||
-         event.GetType() == blink::WebGestureEvent::kGesturePinchEnd;
+  return blink::WebInputEvent::IsPinchGestureEventType(event.GetType());
 }
 
 content::WebContents* AppWebContentsHelper::OpenURLFromTab(