Communicate whether passive event listeners exist to cc.

third_party/WebKit/public/platform/WebEventListenerProperties.h

Index: third_party/WebKit/public/platform/WebEventListenerProperties.h
diff --git a/third_party/WebKit/public/platform/WebEventListenerProperties.h b/third_party/WebKit/public/platform/WebEventListenerProperties.h
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index 0000000000000000000000000000000000000000..56ec72fd5e317a52069c8b8329fb5cb9710ef525
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+++ b/third_party/WebKit/public/platform/WebEventListenerProperties.h
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+// 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.
+
+#ifndef WebEventListenerProperties_h
+#define WebEventListenerProperties_h
+
+#include "WebCommon.h"
+
+namespace blink {
+
+enum class WebEventListenerClass {
+    Touch, // This value includes "pointer" events.
+    MouseWheel // This value includes "wheel" and "mousewheel" events.
+};
+
+// Indicates the variety of event listener types for a given WebEventListenerClass.
+enum class WebEventListenerProperties {
+    Nothing, // This should be "None"; but None #defined in X11's X.h
+    Passive,
+    Blocking, // This indicates >= 1 blocking listener (and >= 0 passive listeners)
+};
+
+} // namespace blink
+
+#endif