The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/92de18119eef5d8046ee5ae88ce7d648ba984181

commit 92de18119eef5d8046ee5ae88ce7d648ba984181
Author: Jian Li <jianli@chromium.org>
Date: Thu Aug 24 00:20:27 2017

Add new MHTML headers to support potential sharing

When a MHTML page is shared, the receiving party may need to find
out and show the basic info about the shared page. We need to
support extracting title and URL easily from the MHTML headers.

Doc:
https://docs.google.com/document/d/1FvmYUC0S0BkdkR7wZsg0hLdKc_qjGnGahBwwa0CdnHE/edit#heading=h.s65c3k7eanp

Bug:  758030 
Change-Id: Ib2882434b4f6f67c4603e197b74dfb725fdc148b
Reviewed-on: https://chromium-review.googlesource.com/627540
Reviewed-by: Dmitry Titov <dimich@chromium.org>
Reviewed-by: Kent Tamura <tkent@chromium.org>
Commit-Queue: Jian Li <jianli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#496885}
[modify] https://crrev.com/92de18119eef5d8046ee5ae88ce7d648ba984181/chrome/android/javatests/src/org/chromium/chrome/browser/offlinepages/OfflinePageBridgeTest.java
[modify] https://crrev.com/92de18119eef5d8046ee5ae88ce7d648ba984181/third_party/WebKit/Source/core/exported/WebFrameSerializer.cpp
[modify] https://crrev.com/92de18119eef5d8046ee5ae88ce7d648ba984181/third_party/WebKit/Source/core/frame/MHTMLTest.cpp
[modify] https://crrev.com/92de18119eef5d8046ee5ae88ce7d648ba984181/third_party/WebKit/Source/platform/mhtml/MHTMLArchive.cpp
[modify] https://crrev.com/92de18119eef5d8046ee5ae88ce7d648ba984181/third_party/WebKit/Source/platform/mhtml/MHTMLArchive.h