Save a few requests for thumb.php for users without profile images

Signed-off-by: Richard Mansfield <richard.mansfield@catalyst.net.nz>

htdocs/artefact/comment/theme/raw/commentlist.tpl

@@ -14,7 +14,7 @@
       <div class="details commentleft">
       {if $item->author}
         <div class="icon"><a href="{$WWWROOT}user/view.php?id={$item->author->id}">
-          <img src="{profile_icon_url user=$item->author maxheight=50 maxwidth=50}" valign="middle" alt="{$item->author|display_name|escape}">
+          <img src="{profile_icon_url user=$item->author maxheight=40 maxwidth=40}" valign="middle" alt="{$item->author|display_name|escape}">
         </a><br />
         <a href="{$WWWROOT}user/view.php?id={$item->author->id}" class="username">{$item->author|display_name|escape}</a></div>
       {else}

htdocs/lib/user.php

@@ -1839,7 +1839,7 @@ function install_system_dashboard_view() {
  * gravatar.
  */
 function profile_icon_url($user, $maxwidth=40, $maxheight=40) {
-    global $USER;
+    global $USER, $THEME;
     static $usercache   = array();
 
     if (is_array($user)) {
@@ -1863,13 +1863,22 @@ function profile_icon_url($user, $maxwidth=40, $maxheight=40) {
     if (!property_exists($user, 'profileicon') || !property_exists($user, 'email')) {
         throw new SystemException('profile_icon_url requires a user with profileicon & email properties');
     }
+    if ($maxwidth != $maxheight || ($maxwidth != 20 && $maxwidth != 40 && $maxwidth != 60)) {
+        log_warn('profile_icon_url should specify maxwidth, maxheight of 20x20, 40x40 or 60x60');
+    }
+
     $thumb = get_config('wwwroot') . 'thumb.php';
     $sizeparams = 'maxwidth=' . $maxwidth . '&maxheight=' . $maxheight;
-    $notfound = $thumb . '?type=profileiconbyid&' . $sizeparams . '&id=0';
+
     if (!empty($user->profileicon)) {
         return $thumb . '?type=profileiconbyid&' . $sizeparams . '&id=' . $user->profileicon;
     }
-    else if (get_config('remoteavatars')) {
+
+    // Assume we have the right size available in docroot, so we don't
+    // have to call thumb.php
+    $notfound = $THEME->get_url('images/no_userphoto' . $maxwidth . '.png');
+
+    if (get_config('remoteavatars')) {
         return remote_avatar($user->email, array('maxw' => $maxwidth, 'maxh' => $maxheight), $notfound);
     }
     return $notfound;