Improved pyside_cache decorator

This one should work properly when multiple properties use the same
callback function.

blender_cloud/blender.py

@@ -45,7 +45,12 @@ def redraw(self, context):
     context.area.tag_redraw()
 
 
-def pyside_cache(wrapped):
+def pyside_cache(propname):
+
+    if callable(propname):
+        raise TypeError('Usage: pyside_cache("property_name")')
+
+    def decorator(wrapped):
         """Stores the result of the callable in Python-managed memory.
 
         This is to work around the warning at
@@ -63,11 +68,13 @@ def pyside_cache(wrapped):
                 result = wrapped(self, context)
                 return result
             finally:
-            wrapped._cached_result = result
+                rna_type, rna_info = getattr(self.bl_rna, propname)
+                rna_info['_cached_result'] = result
         return wrapper
+    return decorator
 
 
-@pyside_cache
+@pyside_cache('version')
 def blender_syncable_versions(self, context):
     """Returns the list of items used by SyncStatusProperties.version EnumProperty."""
 
@@ -130,7 +137,7 @@ class SyncStatusProperties(PropertyGroup):
         self['available_blender_versions'] = new_versions
 
 
-@pyside_cache
+@pyside_cache('project')
 def bcloud_available_projects(self, context):
     """Returns the list of items used by BlenderCloudProjectGroup.project EnumProperty."""