[protobuf mode] Integrate

Issue codemirror#3862

Author: marijnh

doc/compress.html

@@ -181,6 +181,7 @@ <h2>Script compression helper</h2>
           <option value="http://codemirror.net/mode/php/php.js">php.js</option>
           <option value="http://codemirror.net/mode/pig/pig.js">pig.js</option>
           <option value="http://codemirror.net/mode/properties/properties.js">properties.js</option>
+          <option value="http://codemirror.net/mode/protobuf/protobuf.js">protobuf.js</option>
           <option value="http://codemirror.net/mode/python/python.js">python.js</option>
           <option value="http://codemirror.net/mode/puppet/puppet.js">puppet.js</option>
           <option value="http://codemirror.net/mode/q/q.js">q.js</option>

mode/index.html

@@ -104,6 +104,7 @@ <h2>Language modes</h2>
       <li><a href="php/index.html">PHP</a></li>
       <li><a href="pig/index.html">Pig Latin</a></li>
       <li><a href="properties/index.html">Properties files</a></li>
+      <li><a href="protobuf/index.html">ProtoBuf</a></li>
       <li><a href="puppet/index.html">Puppet</a></li>
       <li><a href="python/index.html">Python</a></li>
       <li><a href="q/index.html">Q</a></li>

mode/meta.js

@@ -103,6 +103,7 @@
     {name: "Plain Text", mime: "text/plain", mode: "null", ext: ["txt", "text", "conf", "def", "list", "log"]},
     {name: "PLSQL", mime: "text/x-plsql", mode: "sql", ext: ["pls"]},
     {name: "Properties files", mime: "text/x-properties", mode: "properties", ext: ["properties", "ini", "in"], alias: ["ini", "properties"]},
+    {name: "ProtoBuf", mime: "text/x-protobuf", mode: "protobuf", ext: ["proto"]},
     {name: "Python", mime: "text/x-python", mode: "python", ext: ["py", "pyw"]},
     {name: "Puppet", mime: "text/x-puppet", mode: "puppet", ext: ["pp"]},
     {name: "Q", mime: "text/x-q", mode: "q", ext: ["q"]},

mode/protobuf/protobuf.js

@@ -61,11 +61,7 @@
   };
 
   CodeMirror.defineMode("protobuf", function() {
-    return {
-      token: function(stream) {
-        return tokenBase(stream);
-      }
-    };
+    return {token: tokenBase};
   });
 
   CodeMirror.defineMIME("text/x-protobuf", "protobuf");