RNA: Cleanup PointerRNA struct

The old layout of `PointerRNA` was confusing for historic reasons:
```
typedef struct PointerRNA {
  struct {
    void *data;
  } id;

  struct StructRNA *type;
  void *data;
} PointerRNA;
```

This patch updates it to:
```
typedef struct PointerRNA {
  struct ID *owner_id;
  struct StructRNA *type;
  void *data;
} PointerRNA;
```

Throughout the code base `id.data` was replaced with `owner_id`.
Furthermore, many explicit pointer type casts were added which
were implicit before. Some type casts to `ID *` were removed.

Reviewers: brecht, campbellbarton

Differential Revision: https://developer.blender.org/D5558

1 files changed, 2 insertions, 2 deletions

diff --git a/source/blender/python/intern/bpy_msgbus.c b/source/blender/python/intern/bpy_msgbus.c
index 9db4201c252..630a0392dbd 100644
--- a/source/blender/python/intern/bpy_msgbus.c
+++ b/source/blender/python/intern/bpy_msgbus.c
@@ -269,7 +269,7 @@ static PyObject *bpy_msgbus_subscribe_rna(PyObject *UNUSED(self), PyObject *args
   /* Note: we may want to have a way to pass this in. */
   bContext *C = (bContext *)BPy_GetContext();
   struct wmMsgBus *mbus = CTX_wm_message_bus(C);
-  wmMsgParams_RNA msg_key_params = {{{0}}};
+  wmMsgParams_RNA msg_key_params = {{0}};
 
   wmMsgSubscribeValue msg_val_params = {0};
 
@@ -342,7 +342,7 @@ static PyObject *bpy_msgbus_publish_rna(PyObject *UNUSED(self), PyObject *args,
   /* Note: we may want to have a way to pass this in. */
   bContext *C = (bContext *)BPy_GetContext();
   struct wmMsgBus *mbus = CTX_wm_message_bus(C);
-  wmMsgParams_RNA msg_key_params = {{{0}}};
+  wmMsgParams_RNA msg_key_params = {{0}};
 
   if (py_msgbus_rna_key_from_py(py_sub, &msg_key_params, error_prefix) == -1) {
     return NULL;