Added support for the 'low', 'high', and 'optimum' attributes that the <meter> tag requires.

src/browser/ui/dom/HTMLDOMPropertyConfig.js

@@ -97,6 +97,7 @@ var HTMLDOMPropertyConfig = {
     headers: null,
     height: MUST_USE_ATTRIBUTE,
     hidden: MUST_USE_ATTRIBUTE | HAS_BOOLEAN_VALUE,
+    high: null,
     href: null,
     hrefLang: null,
     htmlFor: null,
@@ -107,6 +108,7 @@ var HTMLDOMPropertyConfig = {
     lang: null,
     list: MUST_USE_ATTRIBUTE,
     loop: MUST_USE_PROPERTY | HAS_BOOLEAN_VALUE,
+    low: null,
     manifest: MUST_USE_ATTRIBUTE,
     marginHeight: null,
     marginWidth: null,
@@ -121,6 +123,7 @@ var HTMLDOMPropertyConfig = {
     name: null,
     noValidate: HAS_BOOLEAN_VALUE,
     open: HAS_BOOLEAN_VALUE,
+    optimum: null,
     pattern: null,
     placeholder: null,
     poster: null,