win: Plumb module PDB name through snapshot

snapshot/module_snapshot.h

Index: snapshot/module_snapshot.h
diff --git a/snapshot/module_snapshot.h b/snapshot/module_snapshot.h
index 6c397ed0a71e6210f988807d8ffea5e9b14ff340..a1bafd92eb006fc33fccb6a5b18e85717d685c97 100644
--- a/snapshot/module_snapshot.h
+++ b/snapshot/module_snapshot.h
@@ -118,8 +118,20 @@ class ModuleSnapshot {
   //! \a age is the number of times the UUID has been reused. This occurs on
   //! Windows with incremental linking. On other platforms \a age will always be
   //! `0`.
+  //!
+  //! \sa DebugFileName()
   virtual void UUIDAndAge(crashpad::UUID* uuid, uint32_t* age) const = 0;
 
+  //! \brief Returns the module’s debug file info name.
+  //!
+  //! On Windows, this references the PDB file, which contains symbol
+  //! information held separately from the module itself. On other platforms,
+  //! this is normally just be the basename of the module, because the debug
+  //! info file’s name is not relevant even in split-debug scenarios.
+  //!
+  //! \sa UUIDAndAge()
+  virtual std::string DebugFileName() const = 0;
+
   //! \brief Returns string annotations recorded in the module.
   //!
   //! This method retrieves annotations recorded in a module. These annotations