Break apart WebGestureEvent from WebInputEvent.

third_party/WebKit/public/platform/WebGestureEvent.h

+// 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 WebGestureEvent_h
+#define WebGestureEvent_h
+
+#include "WebGestureDevice.h"
+#include "WebInputEvent.h"
+
+namespace blink {
+
+// See WebInputEvent.h for details why this pack is here.
+#pragma pack(push, 4)
+
+// WebGestureEvent ---------------------------------------------------------
+
+class WebGestureEvent : public WebInputEvent {
+ public:
+  enum ScrollUnits {
+    PrecisePixels = 0,  // generated by high precision devices.
+    Pixels,             // large pixel jump duration; should animate to delta.
+    Page                // page (visible viewport) based scrolling.
+  };
+
+  enum InertialPhaseState {
+    UnknownMomentumPhase = 0,  // No phase information.
+    NonMomentumPhase,          // Regular scrolling phase.
+    MomentumPhase,             // Momentum phase.
+  };
+
+  int x;
+  int y;
+  int globalX;
+  int globalY;
+  WebGestureDevice sourceDevice;
+
+  // If the WebGestureEvent has sourceDevice=WebGestureDeviceTouchscreen, this
+  // field contains the unique identifier for the touch event that released
+  // this event at TouchDispositionGestureFilter. If the WebGestureEvents was
+  // not released through a touch event (e.g. timer-released gesture events or
+  // gesture events with sourceDevice!=WebGestureDeviceTouchscreen), the field
+  // contains 0. See crbug.com/618738.
+  uint32_t uniqueTouchEventId;
+
+  // This field exists to allow BrowserPlugin to mark GestureScroll events as
+  // 'resent' to handle the case where an event is not consumed when first
+  // encountered; it should be handled differently by the plugin when it is
+  // sent for thesecond time. No code within Blink touches this, other than to
+  // plumb it through event conversions.
+  int resendingPluginId;
+
+  union {
+    // Tap information must be set for GestureTap, GestureTapUnconfirmed,
+    // and GestureDoubleTap events.
+    struct {
+      int tapCount;
+      float width;
+      float height;
+    } tap;
+
+    struct {
+      float width;
+      float height;
+    } tapDown;
+
+    struct {
+      float width;
+      float height;
+    } showPress;
+
+    struct {
+      float width;
+      float height;
+    } longPress;
+
+    struct {
+      float firstFingerWidth;
+      float firstFingerHeight;
+    } twoFingerTap;
+
+    struct {
+      // Initial motion that triggered the scroll.
+      // May be redundant with deltaX/deltaY in the first scrollUpdate.
+      float deltaXHint;
+      float deltaYHint;
+      // Default initialized to ScrollUnits::PrecisePixels.
+      ScrollUnits deltaHintUnits;
+      // If true, this event will skip hit testing to find a scroll
+      // target and instead just scroll the viewport.
+      bool targetViewport;
+      // The state of inertial phase scrolling. OSX has unique phases for normal
+      // and momentum scroll events. Should always be UnknownMomentumPhase for
+      // touch based input as it generates GestureFlingStart instead.
+      InertialPhaseState inertialPhase;
+      // True if this event was synthesized in order to force a hit test;
+      // avoiding scroll latching behavior until crbug.com/526463 is fully
+      // implemented.
+      bool synthetic;
+
+      // number of pointers down.
+      int pointerCount;
+    } scrollBegin;
+
+    struct {
+      float deltaX;
+      float deltaY;
+      float velocityX;
+      float velocityY;
+      // Whether any previous GestureScrollUpdate in the current scroll
+      // sequence was suppressed (e.g., the causal touchmove was
+      // preventDefault'ed). This bit is particularly useful for
+      // determining whether the observed scroll update sequence captures
+      // the entirety of the generative motion.
+      bool previousUpdateInSequencePrevented;
+      bool preventPropagation;
+      InertialPhaseState inertialPhase;
+      // Default initialized to ScrollUnits::PrecisePixels.
+      ScrollUnits deltaUnits;
+    } scrollUpdate;
+
+    struct {
+      // The original delta units the scrollBegin and scrollUpdates
+      // were sent as.
+      ScrollUnits deltaUnits;
+      // The state of inertial phase scrolling. OSX has unique phases for normal
+      // and momentum scroll events. Should always be UnknownMomentumPhase for
+      // touch based input as it generates GestureFlingStart instead.
+      InertialPhaseState inertialPhase;
+      // True if this event was synthesized in order to generate the proper
+      // GSB/GSU/GSE matching sequences. This is a temporary so that a future
+      // GSB will generate a hit test so latching behavior is avoided
+      // until crbug.com/526463 is fully implemented.
+      bool synthetic;
+    } scrollEnd;
+
+    struct {
+      float velocityX;
+      float velocityY;
+      // If true, this event will skip hit testing to find a scroll
+      // target and instead just scroll the viewport.
+      bool targetViewport;
+    } flingStart;
+
+    struct {
+      // If set to true, don't treat flingCancel
+      // as a part of fling boost events sequence.
+      bool preventBoosting;
+    } flingCancel;
+
+    struct {
+      bool zoomDisabled;
+      float scale;
+    } pinchUpdate;
+  } data;
+
+  WebGestureEvent()
+      : WebInputEvent(sizeof(WebGestureEvent)),
+        x(0),
+        y(0),
+        globalX(0),
+        globalY(0),
+        sourceDevice(WebGestureDeviceUninitialized),
+        resendingPluginId(-1) {}
+};
+
+#pragma pack(pop)
+
+}  // namespace blink
+
+#endif  // WebGestureEvent_h