Disable tap suppression logic for WebView

ui/events/gesture_detection/gesture_configuration_android.cc

Index: ui/events/gesture_detection/gesture_configuration_android.cc
diff --git a/ui/events/gesture_detection/gesture_configuration_android.cc b/ui/events/gesture_detection/gesture_configuration_android.cc
index 4922559763277d3197d63f1a4dd12221deb69ef8..30c43d99a46fc2d8d518464ddffc7037a2620b71 100644
--- a/ui/events/gesture_detection/gesture_configuration_android.cc
+++ b/ui/events/gesture_detection/gesture_configuration_android.cc
@@ -52,6 +52,15 @@ class GestureConfigurationAndroid : public GestureConfiguration {
         ViewConfiguration::GetMinScalingTouchMajorInDips());
     set_show_press_delay_in_ms(ViewConfiguration::GetTapTimeoutInMs());
     set_span_slop(ViewConfiguration::GetTouchSlopInDips() * 2.f);
+    set_fling_touchscreen_tap_suppression_enabled(true);
+    set_fling_touchpad_tap_suppression_enabled(false);

[tdresser, 2015/08/04 12:20:50]

If you plug in an external touchpad on Android, do you get fling behavior?

[jdduke (slow), 2015/08/04 17:19:25]

I don't actually know =/, I was about to order an Apple magic trackpad. We would
never get a fling event I don't think, but I wonder if the OS handles such
touchpad flings, or maybe it's even lower level like the driver/firmware (like
on Windows)? We can always enable it when we find the right scenario (though, I
don't think we ever send mouedown/mouseup events yet on Android, so this
probably wouldn't do anything yet).

+    set_fling_max_cancel_to_down_time_in_ms(
+        ViewConfiguration::GetTapTimeoutInMs());
+    set_fling_max_tap_gap_time_in_ms(
+        ViewConfiguration::GetLongPressTimeoutInMs());
+    // There is no "semi" longpress on Android, just use the longpress value.

[tdresser, 2015/08/04 12:20:50]

I think it might be clearer to set this to 0.

[jdduke (slow), 2015/08/04 17:19:25]

Yeah, I went ahead and removed this line, and changed the tap configuration
logic so it uses long_press_time_in_ms instead.

+    set_semi_long_press_time_in_ms(
+        ViewConfiguration::GetLongPressTimeoutInMs());
   }
 
   friend struct DefaultSingletonTraits<GestureConfigurationAndroid>;