Fix HoverButton to respond to GESTURE_TAP events.

Since HoverButton was changed to no longer inherit from MenuButton, the
behavior has to be readded back into the controller.

Bug: 991877
Change-Id: I7d0987eb1b30423753560feee2d8a42bb6d71cc9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1745289Reviewed-by: Peter Boström <pbos@chromium.org>
Commit-Queue: Charlene Yan <cyan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#685383}

chrome/browser/ui/views/hover_button_controller.cc

@@ -54,3 +54,9 @@ void HoverButtonController::OnMouseReleased(const ui::MouseEvent& event) {
     ButtonController::OnMouseReleased(event);
   }
 }
+
+void HoverButtonController::OnGestureEvent(ui::GestureEvent* event) {
+  if (event->type() == ui::ET_GESTURE_TAP && listener_) {
+    listener_->ButtonPressed(button(), *event);
+  }
+}

chrome/browser/ui/views/hover_button_controller.h

@@ -30,6 +30,7 @@ class HoverButtonController : public views::ButtonController {
   bool OnMousePressed(const ui::MouseEvent& event) override;
   void OnMouseReleased(const ui::MouseEvent& event) override;
   bool OnKeyPressed(const ui::KeyEvent& event) override;
+  void OnGestureEvent(ui::GestureEvent* event) override;
 
  private:
   // Listener to be called when button is clicked.