Pass model path to observer (#126503)

Summary: Passing model path to observer so that they can get additional info if needed.

Test Plan: contbuild & OSS CI

Differential Revision: D57475129

Pull Request resolved: https://github.com/pytorch/pytorch/pull/126503
Approved by: https://github.com/kirklandsign
diff --git a/torch/csrc/jit/mobile/import.cpp b/torch/csrc/jit/mobile/import.cpp
index 96ff6c8..da7b87b 100644
--- a/torch/csrc/jit/mobile/import.cpp
+++ b/torch/csrc/jit/mobile/import.cpp
@@ -651,6 +651,10 @@
     std::optional<at::Device> device,
     ExtraFilesMap& extra_files,
     uint64_t module_load_options) {
+  auto observer = torch::observerConfig().getModuleObserver();
+  if (observer) {
+    extra_files.insert(std::make_pair("model_path", filename));
+  }
   auto format = getFileFormat(filename);
 
   if (format == FileFormat::FlatbufferFileFormat) {