avm2: Add infallible methods to get and set dynamic object properties

core/src/avm2/activation.rs

@@ -334,9 +334,7 @@ impl<'a, 'gc> Activation<'a, 'gc> {
         {
             let string_callee = istr!(self, "callee");
 
-            args_object
-                .set_string_property_local(string_callee, callee, self)
-                .unwrap();
+            args_object.set_dynamic_property(string_callee, callee, self.gc());
             args_object.set_local_property_is_enumerable(self.gc(), string_callee, false);
         }
 
@@ -1811,7 +1809,7 @@ impl<'a, 'gc> Activation<'a, 'gc> {
             let value = self.pop_stack();
             let name = self.pop_stack();
 
-            object.set_string_property_local(name.coerce_to_string(self)?, value, self)?;
+            object.set_dynamic_property(name.coerce_to_string(self)?, value, self.gc());
         }
 
         self.push_stack(object);

core/src/avm2/amf.rs

@@ -313,11 +313,20 @@ pub fn deserialize_value_impl<'gc>(
 
             // Now let's add each element as a property
             for element in elements {
-                array.set_string_property_local(
-                    AvmString::new_utf8(activation.gc(), element.name()),
-                    deserialize_value_impl(activation, element.value(), object_map)?,
-                    activation,
-                )?;
+                let name = ruffle_wstr::from_utf8(element.name());
+                let value = deserialize_value_impl(activation, element.value(), object_map)?;
+
+                // If the name of the element was a valid array index, we set an
+                // element on the array instead of setting a dynamic property.
+                if let Some(index) = ArrayObject::as_array_index(&name) {
+                    array.set_element(activation.gc(), index, value);
+                } else {
+                    array.set_dynamic_property(
+                        AvmString::new(activation.gc(), name),
+                        value,
+                        activation.gc(),
+                    );
+                }
             }
             array.into()
         }
@@ -462,7 +471,7 @@ pub fn deserialize_value_impl<'gc>(
                     dict_obj.set_property_by_object(key, value, activation.gc());
                 } else {
                     let key_string = key.coerce_to_string(activation)?;
-                    dict_obj.set_string_property_local(key_string, value, activation)?;
+                    dict_obj.set_dynamic_property(key_string, value, activation.gc());
                 }
             }
             dict_obj.into()
@@ -499,11 +508,11 @@ pub fn deserialize_lso<'gc>(
     let obj = ScriptObject::new_object(activation);
 
     for child in &lso.body {
-        obj.set_string_property_local(
+        obj.set_dynamic_property(
             AvmString::new_utf8(activation.gc(), &child.name),
             deserialize_value(activation, child.value())?,
-            activation,
-        )?;
+            activation.gc(),
+        );
     }
 
     Ok(obj)

core/src/avm2/flv.rs

@@ -15,13 +15,11 @@ fn avm2_object_from_flv_variables<'gc>(
     for value in variables {
         let property_name = value.name;
 
-        info_object
-            .set_string_property_local(
-                AvmString::new_utf8_bytes(activation.gc(), property_name),
-                value.data.to_avm2_value(activation),
-                activation,
-            )
-            .expect("valid set");
+        info_object.set_dynamic_property(
+            AvmString::new_utf8_bytes(activation.gc(), property_name),
+            value.data.to_avm2_value(activation),
+            activation.gc(),
+        );
     }
 
     info_object.into()