Revert "Fix browser menu button flood fill effect always originating from center"

This reverts commit 25016613.

Reason for revert: Speculative revert for
virtual/mouseevent_fractional/fast/events/middleClickAutoscroll-click-hyperlink.html
failure under WebKit Linux Trusty (dbg) .

Original change's description:
> Fix browser menu button flood fill effect always originating from center
> 
> The MenuButton::PressedLock used to be always created with a null
> event from MenuController::Run() causing it to eventually call
> AnimateInkDrop() with a null event, which then used to clear
> the inkdrop host's `last_ripple_triggering_event_` which is
> used as the point from which the flood fill is generated.
> 
> This CL passes the current located event (if any) to
> MenuButton::PressedLock.
> 
> BUG=819878
> 
> Change-Id: I4fb18ab73f60c75af3bce948f44ac41a8c6683b8
> Reviewed-on: https://chromium-review.googlesource.com/1089495
> Reviewed-by: Trent Apted <tapted@chromium.org>
> Commit-Queue: Ahmed Fakhry <afakhry@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#565538}

TBR=tapted@chromium.org,afakhry@chromium.org

Change-Id: Ib3c0639e217e4e62d6c8a1aa004eda721e318c4f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 819878
Reviewed-on: https://chromium-review.googlesource.com/1092249Reviewed-by: Samuel Huang <huangs@chromium.org>
Commit-Queue: Samuel Huang <huangs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565654}

ui/views/controls/menu/menu_controller.cc

@@ -424,11 +424,11 @@ void MenuController::Run(Widget* parent,
   menu_start_time_ = base::TimeTicks::Now();
   menu_start_mouse_press_loc_ = gfx::Point();
 
-  ui::Event* event = nullptr;
   if (parent) {
     View* root_view = parent->GetRootView();
     if (root_view) {
-      event = static_cast<internal::RootView*>(root_view)->current_event();
+      const ui::Event* event =
+          static_cast<internal::RootView*>(root_view)->current_event();
       if (event && event->type() == ui::ET_MOUSE_PRESSED) {
         gfx::Point screen_loc(
             static_cast<const ui::MouseEvent*>(event)->location());
@@ -476,10 +476,8 @@ void MenuController::Run(Widget* parent,
   // Set the selection, which opens the initial menu.
   SetSelection(root, SELECTION_OPEN_SUBMENU | SELECTION_UPDATE_IMMEDIATELY);
 
-  if (button) {
-    pressed_lock_ = std::make_unique<MenuButton::PressedLock>(
-        button, false, ui::LocatedEvent::FromIfValid(event));
-  }
+  if (button)
+    pressed_lock_ = std::make_unique<MenuButton::PressedLock>(button);
 
   if (for_drop_) {
     if (!is_nested_drag) {