Provide default mapping for boilerplate code

lib/handlebars/compiler/javascript-compiler.js

@@ -88,6 +88,7 @@ JavaScriptCompiler.prototype = {
 
     var opcodes = environment.opcodes,
         opcode,
+        firstLoc,
         i,
         l;
 
@@ -95,11 +96,12 @@ JavaScriptCompiler.prototype = {
       opcode = opcodes[i];
 
       this.source.currentLocation = opcode.loc;
+      firstLoc = firstLoc || opcode.loc;
       this[opcode.opcode].apply(this, opcode.args);
     }
 
     // Flush any trailing content that might be pending.
-    this.source.currentLocation = undefined;
+    this.source.currentLocation = firstLoc;
     this.pushSource('');
 
     /* istanbul ignore next */
@@ -135,6 +137,8 @@ JavaScriptCompiler.prototype = {
 
       if (!asObject) {
         ret.compiler = JSON.stringify(ret.compiler);
+
+        this.source.currentLocation = {firstLine: 1, firstColumn: 0};
         ret = this.objectLiteral(ret);
 
         if (options.srcName) {