fix: remove InspectableWebContentsViewMac (#43088)

* fix: remove InspectableWebContentsViewMac (#43033)

* Revert "refactor: remove InspectableWebContentsViewMac in favor of the Views version (#41326)"

This reverts commit e67ab9a93d.

* build: fix gn check

* chore: implement setCornerRadii in inspectable_web_contents_view_mac

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* fix: pass in cornerRadii value in setCornerRadii

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* fix: forward declaration

* 5578714: Remove 0-arg (default) constructor for views::Widget::InitParams.

5578714

* fix: contents_web_view_ -> contents_view_

* chore: remove extraneous includes

---------

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

* fix: remove custom border radius feat (#42320)

* fixup! remove custom border radius feat

---------

Co-authored-by: Shelley Vohr <shelley.vohr@gmail.com>

shell/browser/api/electron_api_web_contents_view.cc

@@ -24,14 +24,29 @@
 #include "ui/views/view_class_properties.h"
 #include "ui/views/widget/widget.h"
 
+#if BUILDFLAG(IS_MAC)
+#include "shell/browser/ui/cocoa/delayed_native_view_host.h"
+#endif
+
 namespace electron::api {
 
 WebContentsView::WebContentsView(v8::Isolate* isolate,
                                  gin::Handle<WebContents> web_contents)
-    : View(web_contents->inspectable_web_contents()->GetView()),
+#if BUILDFLAG(IS_MAC)
+    : View(new DelayedNativeViewHost(web_contents->inspectable_web_contents()
+                                         ->GetView()
+                                         ->GetNativeView())),
+#else
+    : View(web_contents->inspectable_web_contents()->GetView()->GetView()),
+#endif
       web_contents_(isolate, web_contents.ToV8()),
       api_web_contents_(web_contents.get()) {
+#if !BUILDFLAG(IS_MAC)
+  // On macOS the View is a newly-created |DelayedNativeViewHost| and it is our
+  // responsibility to delete it. On other platforms the View is created and
+  // managed by InspectableWebContents.
   set_delete_view(false);
+#endif
   view()->SetProperty(
       views::kFlexBehaviorKey,
       views::FlexSpecification(views::MinimumFlexSizeRule::kScaleToMinimum,