Fix #119030: Only access Location node input when available

Our `node_shader_utils.py` module needs to be updated to account for API
changes made during the 4.0 release cycle [1].

Here we need to guard against accessing the "Location" node input if not
dealing with the appropriate type of Mapping node.

[1] e4ad58114b

Pull Request: https://projects.blender.org/blender/blender/pulls/119354

scripts/modules/bpy_extras/node_shader_utils.py

@@ -36,6 +36,22 @@ def values_clamp(val, minv, maxv):
     else:
         return max(minv, min(maxv, val))
 
+# TODO: Consider moving node_input_value_set/node_input_value_get into a common utility module if
+# more usage merits doing so. If that is done, abstract out the validity check and make it usable
+# for node outputs as well. See PR #119354 for details.
+def node_input_value_set(node, input, value):
+    if node is None or input not in node.inputs:
+        return
+
+    node.inputs[input].default_value = value
+
+
+def node_input_value_get(node, input, default_value=None):
+    if node is None or input not in node.inputs:
+        return default_value
+
+    return node.inputs[input].default_value
+
 
 class ShaderWrapper():
     """
@@ -798,13 +814,11 @@ class ShaderImageTextureWrapper():
     node_mapping = property(node_mapping_get)
 
     def translation_get(self):
-        if self.node_mapping is None:
-            return Vector((0.0, 0.0, 0.0))
-        return self.node_mapping.inputs["Location"].default_value
+        return node_input_value_get(self.node_mapping, "Location", Vector((0.0, 0.0, 0.0)))
 
     @_set_check
     def translation_set(self, translation):
-        self.node_mapping.inputs["Location"].default_value = translation
+        node_input_value_set(self.node_mapping, "Location", translation)
 
     translation = property(translation_get, translation_set)