add method handle

This really needs more checks

androscalpel_serializer/src/file_reader.rs

@@ -184,6 +184,16 @@ impl<'a> DexFileReader<'a> {
             )))
     }
 
+    /// Return a [`MethodHandleItem`] reference from its idx.
+    pub fn get_method_handle(&self, idx: usize) -> Result<&MethodHandleItem> {
+        self.method_handles
+            .get(idx)
+            .ok_or(Error::InconsistantStruct(format!(
+                "method handle {idx} is out of bound (|method_handles|={})",
+                self.method_handles.len()
+            )))
+    }
+
     fn sanity_check(&self) -> Result<()> {
         if self.header.magic.version != [0x30, 0x33, 0x39] {
             warn!(