Clarify determination of active service worker and spec plan

docs/index.bs

@@ -257,15 +257,49 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe
   </section>
 
   <section>
-    <h3 id="selection">Selection and Use</h3>
+    <h3 id="control-and-use">Control and Use</h3>
 
-    A [=/service worker client=] independently <a lt="selection">selects</a> and <a>uses</a> a [=/service worker registration=] for its own loading and its subresources. The <dfn id="dfn-service-worker-registration-selection">selection</dfn> of a [=/service worker registration=], upon a <a>non-subresource request</a>, is a process of either <a lt="Match Service Worker Registration">matching</a> a [=/service worker registration=] from <a>scope to registration map</a> or inheriting an existing [=/service worker registration=] from its parent or owner context depending on the request's [=request/url=].
+    A [=/service worker client=] has an [=active service worker=] that serves its own loading and its subresources. When a [=/service worker client=] has a non-null [=active service worker=], it is said to be <dfn id="dfn-control" lt="controlling|controls|controlled">controlled</dfn> by that [=active service worker=]. When a [=/service worker client=] is [=controlled=] by a [=/service worker=], it is said that the [=/service worker client=] is <dfn id="dfn-use" lt="using|uses|used">using</dfn> the [=/service worker=]’s [=containing service worker registration=].
+    A [=/service worker client=]'s [=active service worker=] is determined as explained in the following subsections.
 
-    When the request's [=request/url=] is not <a lt="is local">local</a>, a [=/service worker client=] <a lt="Match Service Worker Registration">matches</a> a [=/service worker registration=] from <a>scope to registration map</a>. That is, the [=/service worker client=] attempts to consult a [=/service worker registration=] whose [=service worker registration/scope url=] <a lt="Match Service Worker Registration">matches</a> its <a>creation URL</a>.
+    *The rest of the section is non-normative.*
 
-    When the request's [=request/url=] <a>is local</a>, if the [=/service worker client=]'s <a>responsible browsing context</a> is a <a>nested browsing context</a> or the [=/service worker client=] is a <a>worker client</a>, the [=/service worker client=] inherits the [=/service worker registration=] from its <a>parent browsing context</a>'s environment or from the environment of a {{Document}} in the [=/service worker client=]'s [=environment settings object/global object=]'s [=owner set=], respectively, if it exists.
+    Issue: The behavior in this section is not fully specified yet and will be specified in [HTML Standard](https://html.spec.whatwg.org). The work is tracked by the [issue](https://github.com/w3c/ServiceWorker/issues/765) and the [pull request](https://github.com/whatwg/html/pull/2809).
 
-    If the <a>selection</a> was successful, the <a lt="selection">selected</a> [=/service worker registration=]'s <a>active worker</a> starts to <dfn id="dfn-control">control</dfn> the [=/service worker client=]. Otherwise, the flow returns to [=/fetch=] where it falls back to the default behavior. When a [=/service worker client=] is <a>controlled</a> by an <a>active worker</a>, it is considered that the [=/service worker client=] is <dfn id="dfn-use" lt="using|uses|used">using</dfn> the <a>active worker</a>'s <a>containing service worker registration</a>.
+    <section>
+      <h4 id="control-and-use-window-client">The window client case</h4>
+
+      A [=window client=] is [created](https://html.spec.whatwg.org/#set-up-a-window-environment-settings-object) when a [=/browsing context=] is [created](https://html.spec.whatwg.org/#creating-a-new-browsing-context) and when it [=navigates=].
+
+      When a [=window client=] is [created](https://html.spec.whatwg.org/#set-up-a-window-environment-settings-object) in the process of a [=/browsing context=] [creation](https://html.spec.whatwg.org/#creating-a-new-browsing-context):
+
+      If the [=/browsing context=]'s initial [=active document=]'s [=/origin=] is an [=opaque origin=], the [=window client=]'s [=active service worker=] is set to null.
+      Otherwise, it is set to the creator [=document=]'s [=/service worker client=]'s [=active service worker=].
+
+      When a [=window client=] is [created](https://html.spec.whatwg.org/#set-up-a-window-environment-settings-object) in the process of the [=/browsing context=]'s [=navigate|navigation=]:
+
+      If the [=fetch=] is routed through [=/HTTP fetch=], the [=window client=]'s [=active service worker=] is set to the result of the <a lt="Match Service Worker Registration">service worker registration matching</a>.
+      Otherwise, if the created [=document=]'s [=/origin=] is an [=opaque origin=] or not the [=same origin|same=] as its creator [=document=]'s [=/origin=], the [=window client=]'s [=active service worker=] is set to null.
+      Otherwise, it is set to the creator [=document=]'s [=/service worker client=]'s [=active service worker=].
+
+      Note: For an initial [=navigate|navigation=] with [=replacement enabled=], the initial [=window client=] that was [created](https://html.spec.whatwg.org/#set-up-a-window-environment-settings-object) when the [=/browsing context=] was [created](https://html.spec.whatwg.org/#creating-a-new-browsing-context) is reused, but the [=active service worker=] is determined by the same behavior as above.
+
+      Note: [Sandboxed](https://html.spec.whatwg.org/#attr-iframe-sandbox) [=iframes=] without the sandboxing directives, `allow-same-origin` and `allow-scripts`, result in having the [=active service worker=] value of null as their [=/origin=] is an [=opaque origin=]..
+    </section>
+
+    <section>
+      <h4 id="control-and-use-worker-client">The worker client case</h4>
+
+      A [=worker client=] is <a href="https://html.spec.whatwg.org/#set-up-a-worker-environment-settings-object">created</a> when the user agent [=run a worker|runs a worker=].
+
+      When the [=worker client=] is created:
+
+      When the [=fetch=] is routed through [=/HTTP fetch=], the [=worker client=]'s [=active service worker=] is set to the result of the <a lt="Match Service Worker Registration">service worker registration matching</a>.
+      Otherwise, if the [=worker client=]'s [=service worker client/origin=] is an [=opaque origin=], or the [=/request=]'s [=request/URL=] is a [=blob URL=] and the [=worker client=]'s [=service worker client/origin=] is not the [=same origin|same=] as the [=/origin=] of the last item in the [=worker client=]'s [=/global object=]'s [=owner set=], the [=worker client=]'s [=active service worker=] is set to null.
+      Otherwise, it is set to the [=active service worker=] of the [=environment settings object=] of the last [=item=] in the [=worker client=]'s [=/global object=]'s [=owner set=].
+    </section>
+
+    Note: [=Window clients=] and [=worker clients=] with a [data: URL](https://tools.ietf.org/html/rfc2397#section-2) result in having the [=active service worker=] value of null as their [=/origin=] is an [=opaque origin=]. [=Window clients=] and [=worker clients=] with a [=blob URL=] can inherit the [=active service worker=] of their creator [=document=] or owner, but if the [=/request=]'s [=request/origin=] is not the [=same origin|same=] as the [=/origin=] of their creator [=document=] or owner, the [=active service worker=] is set to null.
   </section>
 
   <section>

docs/v1/index.bs

@@ -240,15 +240,49 @@ spec: webappsec-referrer-policy; urlPrefix: https://w3c.github.io/webappsec-refe
   </section>
 
   <section>
-    <h3 id="selection">Selection and Use</h3>
+    <h3 id="control-and-use">Control and Use</h3>
 
-    A [=/service worker client=] independently <a lt="selection">selects</a> and <a>uses</a> a [=/service worker registration=] for its own loading and its subresources. The <dfn id="dfn-service-worker-registration-selection">selection</dfn> of a [=/service worker registration=], upon a <a>non-subresource request</a>, is a process of either <a lt="Match Service Worker Registration">matching</a> a [=/service worker registration=] from <a>scope to registration map</a> or inheriting an existing [=/service worker registration=] from its parent or owner context depending on the request's [=request/url=].
+    A [=/service worker client=] has an [=active service worker=] that serves its own loading and its subresources. When a [=/service worker client=] has a non-null [=active service worker=], it is said to be <dfn id="dfn-control" lt="controlling|controls|controlled">controlled</dfn> by that [=active service worker=]. When a [=/service worker client=] is [=controlled=] by a [=/service worker=], it is said that the [=/service worker client=] is <dfn id="dfn-use" lt="using|uses|used">using</dfn> the [=/service worker=]’s [=containing service worker registration=].
+    A [=/service worker client=]'s [=active service worker=] is determined as explained in the following subsections.
 
-    When the request's [=request/url=] is not <a lt="is local">local</a>, a [=/service worker client=] <a lt="Match Service Worker Registration">matches</a> a [=/service worker registration=] from <a>scope to registration map</a>. That is, the [=/service worker client=] attempts to consult a [=/service worker registration=] whose [=service worker registration/scope url=] <a lt="Match Service Worker Registration">matches</a> its <a>creation URL</a>.
+    *The rest of the section is non-normative.*
 
-    When the request's [=request/url=] <a>is local</a>, if the [=/service worker client=]'s <a>responsible browsing context</a> is a <a>nested browsing context</a> or the [=/service worker client=] is a <a>worker client</a>, the [=/service worker client=] inherits the [=/service worker registration=] from its <a>parent browsing context</a>'s environment or from the environment of a {{Document}} in the [=/service worker client=]'s [=environment settings object/global object=]'s [=owner set=], respectively, if it exists.
+    Note: The behavior in this section is not fully specified yet and will be specified in [HTML Standard](https://html.spec.whatwg.org). The work is tracked by the [issue](https://github.com/w3c/ServiceWorker/issues/765) and the [pull request](https://github.com/whatwg/html/pull/2809). For any Service Workers changes, we will incorporate them into [Service Workers Nightly](https://w3c.github.io/ServiceWorker/).
 
-    If the <a>selection</a> was successful, the <a lt="selection">selected</a> [=/service worker registration=]'s <a>active worker</a> starts to <dfn id="dfn-control">control</dfn> the [=/service worker client=]. Otherwise, the flow returns to [=/fetch=] where it falls back to the default behavior. When a [=/service worker client=] is <a>controlled</a> by an <a>active worker</a>, it is considered that the [=/service worker client=] is <dfn id="dfn-use" lt="using|uses|used">using</dfn> the <a>active worker</a>'s <a>containing service worker registration</a>.
+    <section>
+      <h4 id="control-and-use-window-client">The window client case</h4>
+
+      A [=window client=] is [created](https://html.spec.whatwg.org/#set-up-a-window-environment-settings-object) when a [=/browsing context=] is [created](https://html.spec.whatwg.org/#creating-a-new-browsing-context) and when it [=navigates=].
+
+      When a [=window client=] is [created](https://html.spec.whatwg.org/#set-up-a-window-environment-settings-object) in the process of a [=/browsing context=] [creation](https://html.spec.whatwg.org/#creating-a-new-browsing-context):
+
+      If the [=/browsing context=]'s initial [=active document=]'s [=/origin=] is an [=opaque origin=], the [=window client=]'s [=active service worker=] is set to null.
+      Otherwise, it is set to the creator [=document=]'s [=/service worker client=]'s [=active service worker=].
+
+      When a [=window client=] is [created](https://html.spec.whatwg.org/#set-up-a-window-environment-settings-object) in the process of the [=/browsing context=]'s [=navigate|navigation=]:
+
+      If the [=fetch=] is routed through [=/HTTP fetch=], the [=window client=]'s [=active service worker=] is set to the result of the <a lt="Match Service Worker Registration">service worker registration matching</a>.
+      Otherwise, if the created [=document=]'s [=/origin=] is an [=opaque origin=] or not the [=same origin|same=] as its creator [=document=]'s [=/origin=], the [=window client=]'s [=active service worker=] is set to null.
+      Otherwise, it is set to the creator [=document=]'s [=/service worker client=]'s [=active service worker=].
+
+      Note: For an initial [=navigate|navigation=] with [=replacement enabled=], the initial [=window client=] that was [created](https://html.spec.whatwg.org/#set-up-a-window-environment-settings-object) when the [=/browsing context=] was [created](https://html.spec.whatwg.org/#creating-a-new-browsing-context) is reused, but the [=active service worker=] is determined by the same behavior as above.
+
+      Note: [Sandboxed](https://html.spec.whatwg.org/#attr-iframe-sandbox) [=iframes=] without the sandboxing directives, `allow-same-origin` and `allow-scripts`, result in having the [=active service worker=] value of null as their [=/origin=] is an [=opaque origin=]..
+    </section>
+
+    <section>
+      <h4 id="control-and-use-worker-client">The worker client case</h4>
+
+      A [=worker client=] is <a href="https://html.spec.whatwg.org/#set-up-a-worker-environment-settings-object">created</a> when the user agent [=run a worker|runs a worker=].
+
+      When the [=worker client=] is created:
+
+      When the [=fetch=] is routed through [=/HTTP fetch=], the [=worker client=]'s [=active service worker=] is set to the result of the <a lt="Match Service Worker Registration">service worker registration matching</a>.
+      Otherwise, if the [=worker client=]'s [=service worker client/origin=] is an [=opaque origin=], or the [=/request=]'s [=request/URL=] is a [=blob URL=] and the [=worker client=]'s [=service worker client/origin=] is not the [=same origin|same=] as the [=/origin=] of the last item in the [=worker client=]'s [=/global object=]'s [=owner set=], the [=worker client=]'s [=active service worker=] is set to null.
+      Otherwise, it is set to the [=active service worker=] of the [=environment settings object=] of the last [=item=] in the [=worker client=]'s [=/global object=]'s [=owner set=].
+    </section>
+
+    Note: [=Window clients=] and [=worker clients=] with a [data: URL](https://tools.ietf.org/html/rfc2397#section-2) result in having the [=active service worker=] value of null as their [=/origin=] is an [=opaque origin=]. [=Window clients=] and [=worker clients=] with a [=blob URL=] can inherit the [=active service worker=] of their creator [=document=] or owner, but if the [=/request=]'s [=request/origin=] is not the [=same origin|same=] as the [=/origin=] of their creator [=document=] or owner, the [=active service worker=] is set to null.
   </section>
 
   <section>