PDF bookmarks targets transformed on demand rather than on load.

This decreases load time, especially for PDFs with lots of bookmarks
such as books.

Also, this message is necessary for subsequent changes implementing
nameddests with XYZ positioning.

Bug: 55776,535978,748852
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: Id1d7b87fd8c16b2f748d11bf61b8f78aa80d0b94
Reviewed-on: https://chromium-review.googlesource.com/850924
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>
Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#528717}
12 files changed