chore: regens API reference docs (#889)

diff --git a/docs/dyn/iam_v1.permissions.html b/docs/dyn/iam_v1.permissions.html
index dd64831..d917e3b 100644
--- a/docs/dyn/iam_v1.permissions.html
+++ b/docs/dyn/iam_v1.permissions.html
@@ -75,19 +75,19 @@
 <h1><a href="iam_v1.html">Identity and Access Management (IAM) API</a> . <a href="iam_v1.permissions.html">permissions</a></h1>
 <h2>Instance Methods</h2>
 <p class="toc_element">
-  <code><a href="#queryTestablePermissions">queryTestablePermissions(body, x__xgafv=None)</a></code></p>
+  <code><a href="#queryTestablePermissions">queryTestablePermissions(body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Lists the permissions testable on a resource.</p>
 <p class="toc_element">
   <code><a href="#queryTestablePermissions_next">queryTestablePermissions_next(previous_request, previous_response)</a></code></p>
 <p class="firstline">Retrieves the next page of results.</p>
 <h3>Method Details</h3>
 <div class="method">
-    <code class="details" id="queryTestablePermissions">queryTestablePermissions(body, x__xgafv=None)</code>
+    <code class="details" id="queryTestablePermissions">queryTestablePermissions(body=None, x__xgafv=None)</code>
   <pre>Lists the permissions testable on a resource.
 A permission is testable if it can be tested for an identity on a resource.
 
 Args:
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # A request to get permissions which can be tested on a resource.
@@ -116,12 +116,15 @@
     "permissions": [ # The Permissions testable on the requested resource.
       { # A permission which can be included by a role.
         "apiDisabled": True or False, # The service API associated with the permission is not enabled.
-        "name": "A String", # The name of this Permission.
-        "title": "A String", # The title of this Permission.
-        "stage": "A String", # The current launch stage of the permission.
-        "onlyInPredefinedRoles": True or False, # This permission can ONLY be used in predefined roles.
-        "customRolesSupportLevel": "A String", # The current custom role support level.
         "description": "A String", # A brief description of what this Permission is used for.
+            # This permission can ONLY be used in predefined roles.
+        "title": "A String", # The title of this Permission.
+        "primaryPermission": "A String", # The preferred name for this permission. If present, then this permission is
+            # an alias of, and equivalent to, the listed primary_permission.
+        "name": "A String", # The name of this Permission.
+        "onlyInPredefinedRoles": True or False,
+        "customRolesSupportLevel": "A String", # The current custom role support level.
+        "stage": "A String", # The current launch stage of the permission.
       },
     ],
   }</pre>