chore: regens API reference docs (#889)

diff --git a/docs/dyn/youtube_v3.channels.html b/docs/dyn/youtube_v3.channels.html
index 8df6ca3..865ac98 100644
--- a/docs/dyn/youtube_v3.channels.html
+++ b/docs/dyn/youtube_v3.channels.html
@@ -81,7 +81,7 @@
   <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="#update">update(part, body, onBehalfOfContentOwner=None)</a></code></p>
+  <code><a href="#update">update(part, body=None, onBehalfOfContentOwner=None)</a></code></p>
 <p class="firstline">Updates a channel's metadata. Note that this method currently only supports updates to the channel resource's brandingSettings and invideoPromotion objects and their child properties.</p>
 <h3>Method Details</h3>
 <div class="method">
@@ -119,7 +119,9 @@
       { # A channel resource contains information about a YouTube channel.
         "status": { # JSON template for the status part of a channel. # The status object encapsulates information about the privacy status of the channel.
           "privacyStatus": "A String", # Privacy status of the channel.
+          "selfDeclaredMadeForKids": True or False,
           "isLinked": True or False, # If true, then the user is linked to either a YouTube username or G+ account. Otherwise, the user doesn't have a public YouTube identity.
+          "madeForKids": True or False,
           "longUploadsStatus": "A String", # The long uploads status of this channel. See
         },
         "invideoPromotion": { # Describes an invideo promotion campaign consisting of multiple promoted items. A campaign belongs to a single channel_id. # The invideoPromotion object encapsulates information about promotion campaign associated with the channel.
@@ -293,7 +295,7 @@
         "conversionPings": { # The conversionPings object encapsulates information about conversion pings that need to be respected by the channel. # The conversionPings object encapsulates information about conversion pings that need to be respected by the channel.
           "pings": [ # Pings that the app shall fire (authenticated by biscotti cookie). Each ping has a context, in which the app must fire the ping, and a url identifying the ping.
             { # Pings that the app shall fire (authenticated by biscotti cookie). Each ping has a context, in which the app must fire the ping, and a url identifying the ping.
-              "conversionUrl": "A String", # The url (without the schema) that the player shall send the ping to. It's at caller's descretion to decide which schema to use (http vs https) Example of a returned url: //googleads.g.doubleclick.net/pagead/ viewthroughconversion/962985656/?data=path%3DtHe_path%3Btype%3D cview%3Butuid%3DGISQtTNGYqaYl4sKxoVvKA&labe=default The caller must append biscotti authentication (ms param in case of mobile, for example) to this ping.
+              "conversionUrl": "A String", # The url (without the schema) that the player shall send the ping to. It's at caller's descretion to decide which schema to use (http vs https) Example of a returned url: //googleads.g.doubleclick.net/pagead/ viewthroughconversion/962985656/?data=path%3DtHe_path%3Btype%3D cview%3Butuid%3DGISQtTNGYqaYl4sKxoVvKA&amp;labe=default The caller must append biscotti authentication (ms param in case of mobile, for example) to this ping.
               "context": "A String", # Defines the context of the ping.
             },
           ],
@@ -382,7 +384,7 @@
 </div>
 
 <div class="method">
-    <code class="details" id="update">update(part, body, onBehalfOfContentOwner=None)</code>
+    <code class="details" id="update">update(part, body=None, onBehalfOfContentOwner=None)</code>
   <pre>Updates a channel's metadata. Note that this method currently only supports updates to the channel resource's brandingSettings and invideoPromotion objects and their child properties.
 
 Args:
@@ -391,13 +393,15 @@
 The API currently only allows the parameter value to be set to either brandingSettings or invideoPromotion. (You cannot update both of those parts with a single request.)
 
 Note that this method overrides the existing values for all of the mutable properties that are contained in any parts that the parameter value specifies. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # A channel resource contains information about a YouTube channel.
   "status": { # JSON template for the status part of a channel. # The status object encapsulates information about the privacy status of the channel.
     "privacyStatus": "A String", # Privacy status of the channel.
+    "selfDeclaredMadeForKids": True or False,
     "isLinked": True or False, # If true, then the user is linked to either a YouTube username or G+ account. Otherwise, the user doesn't have a public YouTube identity.
+    "madeForKids": True or False,
     "longUploadsStatus": "A String", # The long uploads status of this channel. See
   },
   "invideoPromotion": { # Describes an invideo promotion campaign consisting of multiple promoted items. A campaign belongs to a single channel_id. # The invideoPromotion object encapsulates information about promotion campaign associated with the channel.
@@ -571,7 +575,7 @@
   "conversionPings": { # The conversionPings object encapsulates information about conversion pings that need to be respected by the channel. # The conversionPings object encapsulates information about conversion pings that need to be respected by the channel.
     "pings": [ # Pings that the app shall fire (authenticated by biscotti cookie). Each ping has a context, in which the app must fire the ping, and a url identifying the ping.
       { # Pings that the app shall fire (authenticated by biscotti cookie). Each ping has a context, in which the app must fire the ping, and a url identifying the ping.
-        "conversionUrl": "A String", # The url (without the schema) that the player shall send the ping to. It's at caller's descretion to decide which schema to use (http vs https) Example of a returned url: //googleads.g.doubleclick.net/pagead/ viewthroughconversion/962985656/?data=path%3DtHe_path%3Btype%3D cview%3Butuid%3DGISQtTNGYqaYl4sKxoVvKA&labe=default The caller must append biscotti authentication (ms param in case of mobile, for example) to this ping.
+        "conversionUrl": "A String", # The url (without the schema) that the player shall send the ping to. It's at caller's descretion to decide which schema to use (http vs https) Example of a returned url: //googleads.g.doubleclick.net/pagead/ viewthroughconversion/962985656/?data=path%3DtHe_path%3Btype%3D cview%3Butuid%3DGISQtTNGYqaYl4sKxoVvKA&amp;labe=default The caller must append biscotti authentication (ms param in case of mobile, for example) to this ping.
         "context": "A String", # Defines the context of the ping.
       },
     ],
@@ -642,7 +646,9 @@
     { # A channel resource contains information about a YouTube channel.
     "status": { # JSON template for the status part of a channel. # The status object encapsulates information about the privacy status of the channel.
       "privacyStatus": "A String", # Privacy status of the channel.
+      "selfDeclaredMadeForKids": True or False,
       "isLinked": True or False, # If true, then the user is linked to either a YouTube username or G+ account. Otherwise, the user doesn't have a public YouTube identity.
+      "madeForKids": True or False,
       "longUploadsStatus": "A String", # The long uploads status of this channel. See
     },
     "invideoPromotion": { # Describes an invideo promotion campaign consisting of multiple promoted items. A campaign belongs to a single channel_id. # The invideoPromotion object encapsulates information about promotion campaign associated with the channel.
@@ -816,7 +822,7 @@
     "conversionPings": { # The conversionPings object encapsulates information about conversion pings that need to be respected by the channel. # The conversionPings object encapsulates information about conversion pings that need to be respected by the channel.
       "pings": [ # Pings that the app shall fire (authenticated by biscotti cookie). Each ping has a context, in which the app must fire the ping, and a url identifying the ping.
         { # Pings that the app shall fire (authenticated by biscotti cookie). Each ping has a context, in which the app must fire the ping, and a url identifying the ping.
-          "conversionUrl": "A String", # The url (without the schema) that the player shall send the ping to. It's at caller's descretion to decide which schema to use (http vs https) Example of a returned url: //googleads.g.doubleclick.net/pagead/ viewthroughconversion/962985656/?data=path%3DtHe_path%3Btype%3D cview%3Butuid%3DGISQtTNGYqaYl4sKxoVvKA&labe=default The caller must append biscotti authentication (ms param in case of mobile, for example) to this ping.
+          "conversionUrl": "A String", # The url (without the schema) that the player shall send the ping to. It's at caller's descretion to decide which schema to use (http vs https) Example of a returned url: //googleads.g.doubleclick.net/pagead/ viewthroughconversion/962985656/?data=path%3DtHe_path%3Btype%3D cview%3Butuid%3DGISQtTNGYqaYl4sKxoVvKA&amp;labe=default The caller must append biscotti authentication (ms param in case of mobile, for example) to this ping.
           "context": "A String", # Defines the context of the ping.
         },
       ],