WIP - Use schema var in validateUpdateCollection instead of ref

Just reduces the number of references for now, this function will need splitting later.

db/collection.go

@@ -320,21 +320,23 @@ func (db *db) validateUpdateCollection(
 		return false, NewErrCollectionIDDoesntMatch(proposedDesc.Name, existingDesc.ID, proposedDesc.ID)
 	}
 
-	if proposedDesc.Schema.SchemaID != existingDesc.Schema.SchemaID {
+	proposedSchema := proposedDesc.Schema
+	existingSchema := existingDesc.Schema
+	if proposedSchema.SchemaID != existingSchema.SchemaID {
 		return false, NewErrSchemaIDDoesntMatch(
 			proposedDesc.Name,
-			existingDesc.Schema.SchemaID,
-			proposedDesc.Schema.SchemaID,
+			existingSchema.SchemaID,
+			proposedSchema.SchemaID,
 		)
 	}
 
-	if proposedDesc.Schema.Name != existingDesc.Schema.Name {
+	if proposedSchema.Name != existingSchema.Name {
 		// There is actually little reason to not support this atm besides controlling the surface area
 		// of the new feature.  Changing this should not break anything, but it should be tested first.
-		return false, NewErrCannotModifySchemaName(existingDesc.Schema.Name, proposedDesc.Schema.Name)
+		return false, NewErrCannotModifySchemaName(existingSchema.Name, proposedSchema.Name)
 	}
 
-	if proposedDesc.Schema.VersionID != "" && proposedDesc.Schema.VersionID != existingDesc.Schema.VersionID {
+	if proposedSchema.VersionID != "" && proposedSchema.VersionID != existingSchema.VersionID {
 		// If users specify this it will be overwritten, an error is prefered to quietly ignoring it.
 		return false, ErrCannotSetVersionID
 	}