Fix ExternalPopupMenu workaround on macOS.

On macOS, ExternalPopupMenu queued a timer event to dispatch an event to the
main frame widget. This is incorrect and assumes that child frame is an
in-process iframe. Instead, the event should be dispatched to the local root
widget.

Change-Id: I9a89496a333c6788621cca305d618900e3c4be88
Bug: 995981
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1775600
Commit-Queue: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Auto-Submit: Erik Chen <erikchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#692195}

third_party/blink/renderer/core/html/forms/external_popup_menu.cc

@@ -39,12 +39,12 @@
 #include "third_party/blink/public/web/web_local_frame_client.h"
 #include "third_party/blink/public/web/web_menu_item_info.h"
 #include "third_party/blink/public/web/web_popup_menu_info.h"
-#include "third_party/blink/public/web/web_view.h"
 #include "third_party/blink/renderer/core/dom/node_computed_style.h"
 #include "third_party/blink/renderer/core/events/current_input_event.h"
 #include "third_party/blink/renderer/core/exported/web_view_impl.h"
 #include "third_party/blink/renderer/core/frame/local_frame.h"
 #include "third_party/blink/renderer/core/frame/local_frame_view.h"
+#include "third_party/blink/renderer/core/frame/web_frame_widget_base.h"
 #include "third_party/blink/renderer/core/frame/web_local_frame_impl.h"
 #include "third_party/blink/renderer/core/html/forms/html_option_element.h"
 #include "third_party/blink/renderer/core/html/forms/html_select_element.h"
@@ -61,11 +61,9 @@
 namespace blink {
 
 ExternalPopupMenu::ExternalPopupMenu(LocalFrame& frame,
-                                     HTMLSelectElement& owner_element,
-                                     WebView& web_view)
+                                     HTMLSelectElement& owner_element)
     : owner_element_(owner_element),
       local_frame_(frame),
-      web_view_(web_view),
       dispatch_event_timer_(frame.GetTaskRunner(TaskType::kInternalDefault),
                             this,
                             &ExternalPopupMenu::DispatchEvent),
@@ -133,9 +131,9 @@ void ExternalPopupMenu::Show() {
 }
 
 void ExternalPopupMenu::DispatchEvent(TimerBase*) {
-  DCHECK(web_view_.MainFrameWidget());
-  web_view_.MainFrameWidget()->HandleInputEvent(
-      blink::WebCoalescedInputEvent(*synthetic_event_));
+  WebLocalFrameImpl::FromFrame(local_frame_)
+      ->FrameWidgetImpl()
+      ->HandleInputEvent(blink::WebCoalescedInputEvent(*synthetic_event_));
   synthetic_event_.reset();
 }
 
@@ -187,6 +185,7 @@ void ExternalPopupMenu::Update() {
 void ExternalPopupMenu::DisconnectClient() {
   Hide();
   owner_element_ = nullptr;
+  dispatch_event_timer_.Stop();
 }
 
 void ExternalPopupMenu::DidChangeSelection(int index) {}

third_party/blink/renderer/core/html/forms/external_popup_menu.h

@@ -44,7 +44,6 @@ class HTMLSelectElement;
 class LocalFrame;
 class WebExternalPopupMenu;
 class WebMouseEvent;
-class WebView;
 struct WebPopupMenuInfo;
 
 // The ExternalPopupMenu is a PopupMenu implementation for macOS and Android.
@@ -52,7 +51,7 @@ struct WebPopupMenuInfo;
 class CORE_EXPORT ExternalPopupMenu final : public PopupMenu,
                                             public WebExternalPopupMenuClient {
  public:
-  ExternalPopupMenu(LocalFrame&, HTMLSelectElement&, WebView&);
+  ExternalPopupMenu(LocalFrame&, HTMLSelectElement&);
   ~ExternalPopupMenu() override;
 
   // Fills |info| with the popup menu information contained in the
@@ -84,7 +83,6 @@ class CORE_EXPORT ExternalPopupMenu final : public PopupMenu,
 
   Member<HTMLSelectElement> owner_element_;
   Member<LocalFrame> local_frame_;
-  WebView& web_view_;
   std::unique_ptr<WebMouseEvent> synthetic_event_;
   TaskRunnerTimer<ExternalPopupMenu> dispatch_event_timer_;
   // The actual implementor of the show menu.

third_party/blink/renderer/core/page/chrome_client_impl.cc

@@ -857,7 +857,7 @@ PopupMenu* ChromeClientImpl::OpenPopupMenu(LocalFrame& frame,
                                            HTMLSelectElement& select) {
   NotifyPopupOpeningObservers();
   if (WebViewImpl::UseExternalPopupMenus())
-    return MakeGarbageCollected<ExternalPopupMenu>(frame, select, *web_view_);
+    return MakeGarbageCollected<ExternalPopupMenu>(frame, select);
 
   DCHECK(RuntimeEnabledFeatures::PagePopupEnabled());
   return MakeGarbageCollected<InternalPopupMenu>(this, select);