Bug 769095. Enforce maximum icon size for nsIAlertsService's notification. r=dao

toolkit/themes/gnomestripe/global/alerts/alert.css

@@ -27,6 +27,11 @@
   min-width: 46px;
 }
 
+#alertImage {
+  max-width: 48px;
+  max-height: 48px;
+}
+
 .alertTitle {
   font-weight: bold;
 }

toolkit/themes/winstripe/global/alerts/alert.css

@@ -32,6 +32,11 @@
   font-weight: bold;
 }
 
+#alertImage {
+  max-width: 48px;
+  max-height: 48px;
+}
+
 .alertText {
   -moz-margin-end: 6px;
 }