Support syntax error feedback in parser.

Now, parser correctly finishes parse procedure if syntax of source code is incorrect (syntax correctness is indicated using return value):
 - parser-internal memory management is performed using jsp_mm_alloc / jsp_mm_free;
 - upon detection of incorrect syntax, all parser-allocated memory regions are deallocated using jsp_mm_free_all and parse finishes with corresponding return value.

JerryScript-DCO-1.0-Signed-off-by: Ruben Ayrapetyan r.ayrapetyan@samsung.com

tests/jerry/eval.js

@@ -86,3 +86,14 @@ for (var i = 0; i < 100; i++)
   r = eval ('if (true) 3; else 5;');
   assert (r === 3);
 }
+
+// Check SyntaxError handling
+try
+{
+  eval ('var var;');
+  assert (false);
+}
+catch (e)
+{
+  assert (e instanceof SyntaxError);
+}