chore: regens API reference docs (#889)

diff --git a/docs/dyn/iam_v1.roles.html b/docs/dyn/iam_v1.roles.html
index 48918af..3310693 100644
--- a/docs/dyn/iam_v1.roles.html
+++ b/docs/dyn/iam_v1.roles.html
@@ -78,13 +78,13 @@
   <code><a href="#get">get(name, x__xgafv=None)</a></code></p>
 <p class="firstline">Gets a Role definition.</p>
 <p class="toc_element">
-  <code><a href="#list">list(parent=None, pageSize=None, showDeleted=None, pageToken=None, x__xgafv=None, view=None)</a></code></p>
+  <code><a href="#list">list(pageSize=None, parent=None, showDeleted=None, pageToken=None, x__xgafv=None, view=None)</a></code></p>
 <p class="firstline">Lists the Roles defined on a resource.</p>
 <p class="toc_element">
   <code><a href="#list_next">list_next(previous_request, previous_response)</a></code></p>
 <p class="firstline">Retrieves the next page of results.</p>
 <p class="toc_element">
-  <code><a href="#queryGrantableRoles">queryGrantableRoles(body, x__xgafv=None)</a></code></p>
+  <code><a href="#queryGrantableRoles">queryGrantableRoles(body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Queries roles that can be granted on a particular resource.</p>
 <p class="toc_element">
   <code><a href="#queryGrantableRoles_next">queryGrantableRoles_next(previous_request, previous_response)</a></code></p>
@@ -95,10 +95,33 @@
   <pre>Gets a Role definition.
 
 Args:
-  name: string, The resource name of the role in one of the following formats:
-`roles/{ROLE_NAME}`
-`organizations/{ORGANIZATION_ID}/roles/{ROLE_NAME}`
-`projects/{PROJECT_ID}/roles/{ROLE_NAME}` (required)
+  name: string, The `name` parameter's value depends on the target resource for the
+request, namely
+[`roles`](/iam/reference/rest/v1/roles),
+[`projects`](/iam/reference/rest/v1/projects.roles), or
+[`organizations`](/iam/reference/rest/v1/organizations.roles). Each
+resource type's `name` value format is described below:
+
+* [`roles.get()`](/iam/reference/rest/v1/roles/get): `roles/{ROLE_NAME}`.
+  This method returns results from all
+  [predefined roles](/iam/docs/understanding-roles#predefined_roles) in
+  Cloud IAM. Example request URL:
+  `https://iam.googleapis.com/v1/roles/{ROLE_NAME}`
+
+* [`projects.roles.get()`](/iam/reference/rest/v1/projects.roles/get):
+  `projects/{PROJECT_ID}/roles/{CUSTOM_ROLE_ID}`. This method returns only
+  [custom roles](/iam/docs/understanding-custom-roles) that have been
+  created at the project level. Example request URL:
+  `https://iam.googleapis.com/v1/projects/{PROJECT_ID}/roles/{CUSTOM_ROLE_ID}`
+
+* [`organizations.roles.get()`](/iam/reference/rest/v1/organizations.roles/get):
+  `organizations/{ORGANIZATION_ID}/roles/{CUSTOM_ROLE_ID}`. This method
+  returns only [custom roles](/iam/docs/understanding-custom-roles) that
+  have been created at the organization level. Example request URL:
+  `https://iam.googleapis.com/v1/organizations/{ORGANIZATION_ID}/roles/{CUSTOM_ROLE_ID}`
+
+Note: Wildcard (*) values are invalid; you must specify a complete project
+ID or organization ID. (required)
   x__xgafv: string, V1 error format.
     Allowed values
       1 - v1 error format
@@ -108,8 +131,8 @@
   An object of the form:
 
     { # A role in the Identity and Access Management API.
-    "description": "A String", # Optional.  A human-readable description for the role.
-    "title": "A String", # Optional.  A human-readable title for the role.  Typically this
+    "description": "A String", # Optional. A human-readable description for the role.
+    "title": "A String", # Optional. A human-readable title for the role.  Typically this
         # is limited to 100 UTF-8 bytes.
     "deleted": True or False, # The current deleted state of the role. This field is read only.
         # It will be ignored in calls to CreateRole and UpdateRole.
@@ -125,21 +148,44 @@
         # When Role is used in CreateRole, the role name must not be set.
         #
         # When Role is used in output and other input such as UpdateRole, the role
-        # name is the complete path, e.g., roles/logging.viewer for curated roles
+        # name is the complete path, e.g., roles/logging.viewer for predefined roles
         # and organizations/{ORGANIZATION_ID}/roles/logging.viewer for custom roles.
   }</pre>
 </div>
 
 <div class="method">
-    <code class="details" id="list">list(parent=None, pageSize=None, showDeleted=None, pageToken=None, x__xgafv=None, view=None)</code>
+    <code class="details" id="list">list(pageSize=None, parent=None, showDeleted=None, pageToken=None, x__xgafv=None, view=None)</code>
   <pre>Lists the Roles defined on a resource.
 
 Args:
-  parent: string, The resource name of the parent resource in one of the following formats:
-`` (empty string) -- this refers to curated roles.
-`organizations/{ORGANIZATION_ID}`
-`projects/{PROJECT_ID}`
   pageSize: integer, Optional limit on the number of roles to include in the response.
+  parent: string, The `parent` parameter's value depends on the target resource for the
+request, namely
+[`roles`](/iam/reference/rest/v1/roles),
+[`projects`](/iam/reference/rest/v1/projects.roles), or
+[`organizations`](/iam/reference/rest/v1/organizations.roles). Each
+resource type's `parent` value format is described below:
+
+* [`roles.list()`](/iam/reference/rest/v1/roles/list): An empty string.
+  This method doesn't require a resource; it simply returns all
+  [predefined roles](/iam/docs/understanding-roles#predefined_roles) in
+  Cloud IAM. Example request URL:
+  `https://iam.googleapis.com/v1/roles`
+
+* [`projects.roles.list()`](/iam/reference/rest/v1/projects.roles/list):
+  `projects/{PROJECT_ID}`. This method lists all project-level
+  [custom roles](/iam/docs/understanding-custom-roles).
+  Example request URL:
+  `https://iam.googleapis.com/v1/projects/{PROJECT_ID}/roles`
+
+* [`organizations.roles.list()`](/iam/reference/rest/v1/organizations.roles/list):
+  `organizations/{ORGANIZATION_ID}`. This method lists all
+  organization-level [custom roles](/iam/docs/understanding-custom-roles).
+  Example request URL:
+  `https://iam.googleapis.com/v1/organizations/{ORGANIZATION_ID}/roles`
+
+Note: Wildcard (*) values are invalid; you must specify a complete project
+ID or organization ID.
   showDeleted: boolean, Include Roles that have been deleted.
   pageToken: string, Optional pagination token returned in an earlier ListRolesResponse.
   x__xgafv: string, V1 error format.
@@ -159,8 +205,8 @@
         # `ListRolesRequest.page_token` to this value.
     "roles": [ # The Roles defined on this resource.
       { # A role in the Identity and Access Management API.
-        "description": "A String", # Optional.  A human-readable description for the role.
-        "title": "A String", # Optional.  A human-readable title for the role.  Typically this
+        "description": "A String", # Optional. A human-readable description for the role.
+        "title": "A String", # Optional. A human-readable title for the role.  Typically this
             # is limited to 100 UTF-8 bytes.
         "deleted": True or False, # The current deleted state of the role. This field is read only.
             # It will be ignored in calls to CreateRole and UpdateRole.
@@ -176,7 +222,7 @@
             # When Role is used in CreateRole, the role name must not be set.
             #
             # When Role is used in output and other input such as UpdateRole, the role
-            # name is the complete path, e.g., roles/logging.viewer for curated roles
+            # name is the complete path, e.g., roles/logging.viewer for predefined roles
             # and organizations/{ORGANIZATION_ID}/roles/logging.viewer for custom roles.
       },
     ],
@@ -198,13 +244,13 @@
 </div>
 
 <div class="method">
-    <code class="details" id="queryGrantableRoles">queryGrantableRoles(body, x__xgafv=None)</code>
+    <code class="details" id="queryGrantableRoles">queryGrantableRoles(body=None, x__xgafv=None)</code>
   <pre>Queries roles that can be granted on a particular resource.
 A role is grantable if it can be used as the role in a binding for a policy
 for that resource.
 
 Args:
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # The grantable role query request.
@@ -232,8 +278,8 @@
         # `QueryGrantableRolesRequest.page_token` to this value.
     "roles": [ # The list of matching roles.
       { # A role in the Identity and Access Management API.
-        "description": "A String", # Optional.  A human-readable description for the role.
-        "title": "A String", # Optional.  A human-readable title for the role.  Typically this
+        "description": "A String", # Optional. A human-readable description for the role.
+        "title": "A String", # Optional. A human-readable title for the role.  Typically this
             # is limited to 100 UTF-8 bytes.
         "deleted": True or False, # The current deleted state of the role. This field is read only.
             # It will be ignored in calls to CreateRole and UpdateRole.
@@ -249,7 +295,7 @@
             # When Role is used in CreateRole, the role name must not be set.
             #
             # When Role is used in output and other input such as UpdateRole, the role
-            # name is the complete path, e.g., roles/logging.viewer for curated roles
+            # name is the complete path, e.g., roles/logging.viewer for predefined roles
             # and organizations/{ORGANIZATION_ID}/roles/logging.viewer for custom roles.
       },
     ],