chore: remove native_mate (Part 11) (#20719)

* refactor: convert Menu and globalShortcut to gin

* refactor: convert api::Cookies to gin

* refactor: convert View and WebContentsView to gin

* refactor: convert WebContents related classes to gin

* refactor: convert powerMonitor to gin

* refactor: prepare for header change

* refactor: remove last uses of mate::EventEmitter

* refactor: remove mate::EventEmitter

* refactor: move trackable_object to gin_helper

* fix: custom converter should not use Handle

* fix: no more need to check if icon is empty

It was a bug that the Handle<NativeImage> can be non-empty when the
image file does not exist. The bug was caused by the converter code
writing out the image even when the convertion fails.

The bug was work-arounded by adding an additional check, but since the
original bug had been fixed, the additional check is no longer needed.

* fix: should always set frameId even when callback is null

* fix: do not mix gin/mate handles for NativeImage

shell/common/api/atom_api_native_image_mac.mm

@@ -33,7 +33,7 @@ double safeShift(double in, double def) {
   return def;
 }
 
-mate::Handle<NativeImage> NativeImage::CreateFromNamedImage(
+gin::Handle<NativeImage> NativeImage::CreateFromNamedImage(
     gin::Arguments* args,
     const std::string& name) {
   @autoreleasepool {