Define return types for new algs; don't export partition check

index.bs

@@ -1526,7 +1526,8 @@ an [=empty host=], and a [=url/path=] consisting of one element itself also a [=
 
 <div algorithm="obtainBlobObject">
 To <dfn export id=blob-url-obtain-object>obtain a blob object</dfn> given a [=blob URL entry=]
-|blobUrlEntry|, an [=environment settings object=] or the string "`navigation`" |environment|:
+|blobUrlEntry| and an [=environment settings object=] or the string "`navigation`" |environment|,
+perform the following steps. They return an [=blob URL entry/object=].
 
 1. Let |isAuthorized| be true.
 1. If |environment| is not the string "`navigation`", then set |isAuthorized| to the result of [=checking for same-partition blob URL usage=] with |blobUrlEntry| and |environment|.
@@ -1616,7 +1617,7 @@ the environment where the <a>blob URL</a> was created. <a>Blob URL</a> navigatio
 to this restriction.
 
 <div algorithm="checkForSamePartitionBlobUrlUsage">
-To <dfn export id=blob-url-partition-check>check for same-partition blob URL usage</dfn> given a [=blob URL entry=] |blobUrlEntry| and an [=environment settings object=] |environment|:
+To <dfn>check for same-partition blob URL usage</dfn> given a [=blob URL entry=] |blobUrlEntry| and an [=environment settings object=] |environment|, perform the following steps. They return a boolean.
 
 1. Let |blobStorageKey| be the result of [=obtaining a storage key for non-storage purposes=] with |blobUrlEntry|'s [=blob URL entry/environment=].
 1. Let |environmentStorageKey| be the result of [=obtaining a storage key for non-storage purposes=] with |environment|.