[Android] More eager gesture recognition hardening

content/browser/android/content_view_core_impl.cc

Index: content/browser/android/content_view_core_impl.cc
diff --git a/content/browser/android/content_view_core_impl.cc b/content/browser/android/content_view_core_impl.cc
index 382db082ec38eaec66f344b737c010195ad0ca3a..fcb5478243d5c5bf9b355566212f6e8f027f5ae0 100644
--- a/content/browser/android/content_view_core_impl.cc
+++ b/content/browser/android/content_view_core_impl.cc
@@ -1030,7 +1030,12 @@ void ContentViewCoreImpl::OnTouchEventHandlingBegin(JNIEnv* env,
 }
 
 void ContentViewCoreImpl::OnTouchEventHandlingEnd(JNIEnv* env, jobject obj) {
-  DCHECK(handling_touch_event_);
+  if (!handling_touch_event_)
+    return;
+
+  GestureEventPacket gesture_packet;
+  std::swap(gesture_packet, pending_gesture_packet_);
+
   handling_touch_event_ = false;
 
   RenderWidgetHostViewAndroid* rwhv = GetRenderWidgetHostViewAndroid();
@@ -1039,8 +1044,7 @@ void ContentViewCoreImpl::OnTouchEventHandlingEnd(JNIEnv* env, jobject obj) {
 
   // Note: Order is important here, as the touch may be ack'ed synchronously
   TouchDispositionGestureFilter::PacketResult result =
-      touch_disposition_gesture_filter_.OnGestureEventPacket(
-          pending_gesture_packet_);
+      touch_disposition_gesture_filter_.OnGestureEventPacket(gesture_packet);
   if (result != TouchDispositionGestureFilter::SUCCESS) {
     NOTREACHED() << "Invalid touch gesture sequence detected.";
     return;