crash reporter: remember email, helps with feedback

src/www/crash_reporter.php

@@ -93,6 +93,14 @@ if (isset($_POST['Submit'])) {
         $email = trim($_POST['Email']);
         if (!empty($email)) {
             $crash_report_header .= "Email {$email}\n";
+            if (!isset($config['system']['contact_email']) ||
+                $config['system']['contact_email'] !== $email) {
+                $config['system']['contact_email'] = $email;
+                write_config('Updated crash reporter contact email.');
+            }
+        } elseif (isset($config['system']['contact_email'])) {
+            unset($config['system']['contact_email']);
+            write_config('Removed crash reporter contact email.');
         }
         $desc = trim($_POST['Desc']);
         if (!empty($desc)) {
@@ -117,6 +125,8 @@ if (isset($_POST['Submit'])) {
     $has_crashed = get_crash_report(true) != '';
 }
 
+$email = isset($config['system']['contact_email']) ? $config['system']['contact_email'] : '';
+
 if ($has_crashed) {
     $crash_files = glob("/var/crash/*");
     $crash_reports['System Information'] = trim($crash_report_header);
@@ -158,7 +168,7 @@ if ($has_crashed) {
     echo "<p>" . gettext("Would you like to submit this crash report to the developers?") . "</p>";
     echo '<hr><p>' . gettext('You can help us further by adding your contact information and a problem description. ' .
         'Please note that providing your contact information greatly improves the chances of bugs being fixed.') . '</p>';
-    echo sprintf('<p><input type="text" placeholder="%s" name="Email"></p>', gettext('your@email.com'));
+    echo sprintf('<p><input type="text" placeholder="%s" name="Email" value="%s"></p>', gettext('your@email.com'), $email);
     echo sprintf('<p><textarea rows="5" placeholder="%s" name="Desc"></textarea></p>', gettext('A short problem description or steps to reproduce.'));
     echo "<hr><p>" . gettext("Please double-check the following contents to ensure you are comfortable submitting the following information.") . "</p>";
     foreach ($crash_reports as $report => $content) {