Partition cache API by storage key. (#1606) (#1630)

Author: wanderview

docs/index.bs

@@ -1827,9 +1827,9 @@ spec: storage; urlPrefix: https://storage.spec.whatwg.org/
 
     A <dfn id="dfn-name-to-cache-map">name to cache map</dfn> is an <a>ordered map</a> whose [=map/entry=] consists of a [=map/key=] (a string that represents the name of a [=request response list=]) and a [=map/value=] (a [=request response list=]).
 
-    Each [=/origin=] has an associated [=name to cache map=].
+    Each [=/storage key=] has an associated [=name to cache map=].
 
-    The <dfn id="dfn-relevant-name-to-cache-map">relevant name to cache map</dfn> is the instance of [=this=]'s associated [=CacheStorage/global object=]'s [=environment settings object=]'s [=environment settings object/origin=].
+    The <dfn id="dfn-relevant-name-to-cache-map">relevant name to cache map</dfn> is the [=name to cache map=] associated with the [=/storage key=] [=obtain a storage key|obtained=] from [=this=]'s associated [=CacheStorage/global object=]'s [=environment settings object=].
   </section>
 
   <section>