idl_parser: Support annotated types in OptionalType (Iterable's value type)

This CL's intention is to adjust to the change of WebIDL's specification.

Before this CL, Iterable's value types cannot be annotated.

After this CL, however, Iterable's value types can be annotated types.

In order to check if ASTs are dumped correctly, I also added pattern match based tests.

Bug: 714866
Change-Id: I4e5cb09f36b6b7c04b7a0d3a32cff085691bcdc6
Reviewed-on: https://chromium-review.googlesource.com/662979Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Hitoshi Yoshida <peria@chromium.org>
Reviewed-by: Kenichi Ishibashi <bashi@chromium.org>
Commit-Queue: Kenichi Ishibashi <bashi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#501488}

tools/idl_parser/idl_parser.py

@@ -732,7 +732,7 @@ class IDLParser(object):
     p[0] = self.BuildProduction('Iterable', p, 2, childlist)
 
   def p_OptionalType(self, p):
-    """OptionalType : ',' Type
+    """OptionalType : ',' TypeWithExtendedAttributes
                     |"""
     if len(p) > 1:
       p[0] = p[2]

tools/idl_parser/test_parser/interface_web.idl

@@ -324,6 +324,15 @@ interface MyIfacePromise {
  *      ExtAttributes()
  *        ExtAttribute(Clamp)
  *        ExtAttribute(XAttr)
+ *  Iterable()
+ *    Type()
+ *      PrimitiveType(long)
+ *      ExtAttributes()
+ *        ExtAttribute(Clamp)
+ *    Type()
+ *      PrimitiveType(long long)
+ *      ExtAttributes()
+ *        ExtAttribute(EnforceRange)
  */
 interface MyIfaceIterable {
   iterable<long>;
@@ -331,6 +340,7 @@ interface MyIfaceIterable {
   iterable<[Clamp] long>;
   iterable<[TreatNullAs=EmptyString] DOMString>;
   iterable<[Clamp, XAttr] long>;
+  iterable<[Clamp] long, [EnforceRange] long long>;
 };
 
 /** TREE