[Export] Use image loader directly to avoid "resource as image file" errors.

(cherry picked from commit 908bef8eee145408bbf660e873279a978a0acb74)

platform/iphone/export/export.cpp

@@ -947,7 +947,7 @@ Error EditorExportPlatformIOS::_export_loading_screen_file(const Ref<EditorExpor
 		Ref<Image> image;
 		String image_path = p_dest_dir.plus_file("[email protected]");
 		image.instance();
-		Error err = image->load(custom_launch_image_2x);
+		Error err = ImageLoader::load_image(custom_launch_image_2x, image);
 
 		if (err) {
 			image.unref();
@@ -961,7 +961,7 @@ Error EditorExportPlatformIOS::_export_loading_screen_file(const Ref<EditorExpor
 		image.unref();
 		image_path = p_dest_dir.plus_file("[email protected]");
 		image.instance();
-		err = image->load(custom_launch_image_3x);
+		err = ImageLoader::load_image(custom_launch_image_3x, image);
 
 		if (err) {
 			image.unref();
@@ -978,7 +978,7 @@ Error EditorExportPlatformIOS::_export_loading_screen_file(const Ref<EditorExpor
 
 		if (!splash_path.empty()) {
 			splash.instance();
-			const Error err = splash->load(splash_path);
+			const Error err = ImageLoader::load_image(splash_path, splash);
 			if (err) {
 				splash.unref();
 			}

platform/osx/export/export.cpp

@@ -31,6 +31,7 @@
 #include "export.h"
 #include "codesign.h"
 
+#include "core/io/image_loader.h"
 #include "core/io/marshalls.h"
 #include "core/io/resource_saver.h"
 #include "core/io/zip_io.h"
@@ -1180,8 +1181,8 @@ Error EditorExportPlatformOSX::export_project(const Ref<EditorExportPreset> &p_p
 				} else {
 					Ref<Image> icon;
 					icon.instance();
-					icon->load(iconpath);
-					if (!icon->empty()) {
+					err = ImageLoader::load_image(iconpath, icon);
+					if (err == OK && !icon->empty()) {
 						_make_icon(p_preset, icon, data);
 					}
 				}