Route touch-events for WebViewGuest directly to guest renderer.

content/renderer/browser_plugin/browser_plugin.cc

Index: content/renderer/browser_plugin/browser_plugin.cc
diff --git a/content/renderer/browser_plugin/browser_plugin.cc b/content/renderer/browser_plugin/browser_plugin.cc
index 0af3aa46a282f9d219d83b8061dcb4bcea81cc89..60451d6a9d6dbc53dbf241f339836922e2cf5496 100644
--- a/content/renderer/browser_plugin/browser_plugin.cc
+++ b/content/renderer/browser_plugin/browser_plugin.cc
@@ -84,6 +84,8 @@ BrowserPlugin::BrowserPlugin(
 }
 
 BrowserPlugin::~BrowserPlugin() {
+  Detach();
+
   if (compositing_helper_.get())
     compositing_helper_->OnContainerDestroy();
 
@@ -489,6 +491,8 @@ blink::WebInputEventResult BrowserPlugin::handleInputEvent(
   if (guest_crashed_ || !attached())
     return blink::WebInputEventResult::NotHandled;
 
+  DCHECK(!blink::WebInputEvent::isTouchEventType(event.type));
+
   if (event.type == blink::WebInputEvent::MouseWheel) {
     auto wheel_event = static_cast<const blink::WebMouseWheelEvent&>(event);
     if (wheel_event.resendingPluginId == browser_plugin_instance_id_)