test: migrate shell specs to main process (#35058)

shell/common/api/electron_api_shell.cc

@@ -15,6 +15,7 @@
 #include "shell/common/platform_util.h"
 
 #if BUILDFLAG(IS_WIN)
+#include "base/threading/thread_restrictions.h"
 #include "base/win/scoped_com_initializer.h"
 #include "base/win/shortcut.h"
 
@@ -105,6 +106,11 @@ v8::Local<v8::Promise> TrashItem(v8::Isolate* isolate,
 }
 
 #if BUILDFLAG(IS_WIN)
+// The use of the ForTesting flavors is a hack workaround to avoid having to
+// patch these as friends into the associated guard classes.
+class ShortcutAccessScopedAllowBlocking
+    : public base::ScopedAllowBlockingForTesting {};
+
 bool WriteShortcutLink(const base::FilePath& shortcut_path,
                        gin_helper::Arguments* args) {
   base::win::ShortcutOperation operation =
@@ -136,6 +142,7 @@ bool WriteShortcutLink(const base::FilePath& shortcut_path,
   if (options.Get("toastActivatorClsid", &toastActivatorClsid))
     properties.set_toast_activator_clsid(toastActivatorClsid);
 
+  ShortcutAccessScopedAllowBlocking allow_blocking;
   base::win::ScopedCOMInitializer com_initializer;
   return base::win::CreateOrUpdateShortcutLink(shortcut_path, properties,
                                                operation);
@@ -145,6 +152,7 @@ v8::Local<v8::Value> ReadShortcutLink(gin_helper::ErrorThrower thrower,
                                       const base::FilePath& path) {
   using base::win::ShortcutProperties;
   gin::Dictionary options = gin::Dictionary::CreateEmpty(thrower.isolate());
+  ShortcutAccessScopedAllowBlocking allow_blocking;
   base::win::ScopedCOMInitializer com_initializer;
   base::win::ShortcutProperties properties;
   if (!base::win::ResolveShortcutProperties(