Small performance fixes

According to the discussion in vuejs#262

Author: bpierre

src/compiler.js

@@ -525,17 +525,18 @@ CompilerProto.compileElement = function (node, root) {
         var prefix = config.prefix + '-',
             attrs = slice.call(node.attributes),
             params = this.options.paramAttributes,
-            attr, isDirective, exp, directives, directive, dirname
+            attr, attrname, isDirective, exp, directives, directive, dirname
 
         for (i = 0, l = attrs.length; i < l; i++) {
 
             attr = attrs[i]
+            attrname = attr.name
             isDirective = false
 
-            if (attr.name.indexOf(prefix) === 0) {
+            if (attrname.indexOf(prefix) === 0) {
                 // a directive - split, parse and bind it.
                 isDirective = true
-                dirname = attr.name.slice(prefix.length)
+                dirname = attrname.slice(prefix.length)
                 // build with multiple: true
                 directives = this.parseDirective(dirname, attr.value, node, true)
                 // loop through clauses (separated by ",")
@@ -553,8 +554,8 @@ CompilerProto.compileElement = function (node, root) {
                 exp = TextParser.parseAttr(attr.value)
                 if (exp) {
                     directive = this.parseDirective('attr', exp, node)
-                    directive.arg = attr.name
-                    if (params && params.indexOf(attr.name) > -1) {
+                    directive.arg = attrname
+                    if (params && params.indexOf(attrname) > -1) {
                         // a param attribute... we should use the parent binding
                         // to avoid circular updates like size={{size}}
                         this.bindDirective(directive, this.parent)
@@ -565,7 +566,7 @@ CompilerProto.compileElement = function (node, root) {
             }
 
             if (isDirective && dirname !== 'cloak') {
-                node.removeAttribute(attr.name)
+                node.removeAttribute(attrname)
             }
         }
 

src/directive.js

@@ -162,7 +162,7 @@ Directive.parse = function (str) {
             arg = str.slice(begin, i).trim()
             if (ARG_RE.test(arg)) {
                 argIndex = i + 1
-                dir.arg = str.slice(begin, i).trim()
+                dir.arg = arg
             }
         } else if (c === '|' && str.charAt(i + 1) !== '|' && str.charAt(i - 1) !== '|') {
             if (dir.key === undefined) {