Allow spaces in types for decl_storage proc_macro (#1245)

* Do not try to fix type display for metadata in rust.

* Fix test (adding extra space (we can see it as a canary: if at some
point quote got a better output the test will fail and js space removal
could be remove)).

substrate/srml/support/src/storage/generator.rs

@@ -677,7 +677,7 @@ mod tests {
 			StorageFunctionMetadata {
 				name: DecodeDifferent::Encode("GETU32"),
 				modifier: StorageFunctionModifier::Default,
-				ty: StorageFunctionType::Plain(DecodeDifferent::Encode("T::Origin")),
+				ty: StorageFunctionType::Plain(DecodeDifferent::Encode("T :: Origin")),
 				documentation: DecodeDifferent::Encode(&[]),
 			},
 			StorageFunctionMetadata {