Do not flush subexpressions

They are no longer duplicated with the new helper calling pattern and this also introduced stack corruption issues due to improper value lookups.

Fixes #767
Fixes #768

lib/handlebars/compiler/javascript-compiler.js

@@ -545,13 +545,6 @@ JavaScriptCompiler.prototype = {
 
     var lookup = (isSimple ? helper.name + ' || ' : '') + nonHelper + ' || helperMissing';
     this.push('((' + lookup + ').call(' + helper.callParams + '))');
-
-    // Always flush subexpressions. This is both to prevent the compounding size issue that
-    // occurs when the code has to be duplicated for inlining and also to prevent errors
-    // due to the incorrect options object being passed due to the shared register.
-    if (!isRoot) {
-      this.flushInline();
-    }
   },
 
   // [invokeKnownHelper]