[Picture-in-Picture] Add PictureInPictureWindow resize event stub

This CL prepares the PictureInPictureWindow interface by adding the
|resize| event handler to PictureInPictureWindow. We currently don't
receive resize events from the backend. Triggering |resize| event will
come in a future CL.

Bug: 806249
Change-Id: Ib10eabc0e35af782dcdb36862535063d2dab0a2c
Reviewed-on: https://chromium-review.googlesource.com/908562Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Reviewed-by: apacible <apacible@chromium.org>
Commit-Queue: Mounir Lamouri <mlamouri@chromium.org>
Cr-Commit-Position: refs/heads/master@{#536703}

third_party/WebKit/LayoutTests/webexposed/global-interface-listing-expected.txt

@@ -5105,11 +5105,13 @@ interface PhotoCapabilities
     getter imageWidth
     getter redEyeReduction
     method constructor
-interface PictureInPictureWindow
+interface PictureInPictureWindow : EventTarget
     attribute @@toStringTag
     getter height
+    getter onresize
     getter width
     method constructor
+    setter onresize
 interface Plugin
     attribute @@toStringTag
     getter description

third_party/WebKit/Source/modules/event_target_modules_names.json5

@@ -31,6 +31,7 @@
     "modules/payments/PaymentRequest",
     "modules/permissions/PermissionStatus",
     "modules/picture_in_picture/HTMLVideoElementPictureInPicture",
+    "modules/picture_in_picture/PictureInPictureWindow",
     "modules/presentation/PresentationAvailability",
     "modules/presentation/PresentationConnection",
     "modules/presentation/PresentationConnectionList",

third_party/WebKit/Source/modules/picture_in_picture/PictureInPictureController.cpp

@@ -102,7 +102,8 @@ PictureInPictureController::CreatePictureInPictureWindow(int width,
   if (picture_in_picture_window_)
     picture_in_picture_window_->OnClose();
 
-  picture_in_picture_window_ = new PictureInPictureWindow(width, height);
+  picture_in_picture_window_ =
+      new PictureInPictureWindow(GetSupplementable(), width, height);
   return picture_in_picture_window_;
 }
 

third_party/WebKit/Source/modules/picture_in_picture/PictureInPictureWindow.cpp

@@ -4,14 +4,28 @@
 
 #include "modules/picture_in_picture/PictureInPictureWindow.h"
 
+#include "core/dom/ExecutionContext.h"
+
 namespace blink {
 
-PictureInPictureWindow::PictureInPictureWindow(int width, int height)
-    : width_(width), height_(height) {}
+PictureInPictureWindow::PictureInPictureWindow(
+    ExecutionContext* execution_context,
+    int width,
+    int height)
+    : ContextClient(execution_context), width_(width), height_(height) {}
 
 void PictureInPictureWindow::OnClose() {
   width_ = 0;
   height_ = 0;
 }
 
+const AtomicString& PictureInPictureWindow::InterfaceName() const {
+  return EventTargetNames::PictureInPictureWindow;
+}
+
+void PictureInPictureWindow::Trace(blink::Visitor* visitor) {
+  EventTargetWithInlineData::Trace(visitor);
+  ContextClient::Trace(visitor);
+}
+
 }  // namespace blink

third_party/WebKit/Source/modules/picture_in_picture/PictureInPictureWindow.h

@@ -5,7 +5,8 @@
 #ifndef PictureInPictureWindow_h
 #define PictureInPictureWindow_h
 
-#include "platform/bindings/ScriptWrappable.h"
+#include "core/dom/ExecutionContext.h"
+#include "modules/EventTargetModules.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
@@ -13,11 +14,13 @@ namespace blink {
 // The PictureInPictureWindow is meant to be used only by
 // PictureInPictureController and is fundamentally just a simple proxy to get
 // information such as dimensions about the current Picture-in-Picture window.
-class PictureInPictureWindow : public ScriptWrappable {
+class PictureInPictureWindow : public EventTargetWithInlineData,
+                               public ContextClient {
+  USING_GARBAGE_COLLECTED_MIXIN(PictureInPictureWindow);
   DEFINE_WRAPPERTYPEINFO();
 
  public:
-  PictureInPictureWindow(int width, int height);
+  PictureInPictureWindow(ExecutionContext*, int width, int height);
 
   int width() const { return width_; }
   int height() const { return height_; }
@@ -25,6 +28,16 @@ class PictureInPictureWindow : public ScriptWrappable {
   // Called when Picture-in-Picture window state is closed.
   void OnClose();
 
+  DEFINE_ATTRIBUTE_EVENT_LISTENER(resize);
+
+  // EventTarget overrides.
+  const AtomicString& InterfaceName() const override;
+  ExecutionContext* GetExecutionContext() const override {
+    return ContextClient::GetExecutionContext();
+  }
+
+  void Trace(blink::Visitor*) override;
+
  private:
   // The Picture-in-Picture window width in pixels.
   int width_;

third_party/WebKit/Source/modules/picture_in_picture/PictureInPictureWindow.idl

@@ -6,10 +6,9 @@
 [
     RuntimeEnabled=PictureInPictureAPI
 ]
-interface PictureInPictureWindow {
+interface PictureInPictureWindow : EventTarget {
   readonly attribute long width;
   readonly attribute long height;
 
-  // TODO(crbug.com/806249): Implement PiP window resize event.
-  // attribute EventHandler onresize;
+  attribute EventHandler onresize;
 };
\ No newline at end of file