IDL parser: IDL parser should use None for indentifier of unnamed operations

IDL parser uses '_unnamed_' as identifier of unnamed operations
in Web IDL, while '_unnamed_' can be a valid identifier in spec.
So replacing '_unnamed_' identifier with empty string.

Bug: 764184
Change-Id: Idfcde792d8665932d15dcae1ae65f2c66a247025
Reviewed-on: https://chromium-review.googlesource.com/685114
Commit-Queue: srirama chandra sekhar <srirama.m@samsung.com>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Kenichi Ishibashi <bashi@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#504644}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 201c7ba63cdee933b58dbe53b962b10b2637d25f
2 files changed