Use objects for hash value tracking

The use of arrays was incorrect for the data type and causing problems when hash keys conflicted with array behaviors.

Fixes #1194

(cherry picked from commit 768ddbd661)

lib/handlebars/compiler/javascript-compiler.js

@@ -543,7 +543,7 @@ JavaScriptCompiler.prototype = {
     if (this.hash) {
       this.hashes.push(this.hash);
     }
-    this.hash = {values: [], types: [], contexts: [], ids: []};
+    this.hash = {values: {}, types: [], contexts: [], ids: []};
   },
   popHash: function() {
     let hash = this.hash;