Would it be possible to provide quantitative data about the cost in bytes of one update for Flash and Chrome stable respectively? It does not affect what I am doing but it is good to have the data just in case.

This bug breaks down into two pieces:
#1: Update pepper_flash_component_installer.cc to support GetInstalledFile so that we can attempt patching operations.
#2: Whitelist MIMOJJLKMOIJPICAKMNDHOIGIMIGCMBB server side for delta updates.

After this, we will begin generating differential updates immediately following the config push. It would be good to also:

#3 Adjust the flash release process so that the service creates the diffs prior to any push. [I will follow up on this internally once we have 1 and 2 done.]

Re: #1 - Yes; I have data, will follow up internally. (Or we can R-V-G this bug.)

Adding RVG to afford data sharing on the issue.

Issue 466792 has been merged into this issue.

Moving this nonessential bug to the next milestone.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/58f1f45cb86735c30e2787358cd3a0827fc8cde4

commit 58f1f45cb86735c30e2787358cd3a0827fc8cde4
Author: waffles <waffles@chromium.org>
Date: Tue Jun 21 16:48:50 2016

Add manifest.json to Flash output for Mac.

This file is needed to unify how the updater finds the version on disk
as well as a base for differential updates.

BUG= 601928 

Review-Url: https://codereview.chromium.org/2080313004
Cr-Commit-Position: refs/heads/master@{#401016}

[modify] https://crrev.com/58f1f45cb86735c30e2787358cd3a0827fc8cde4/chrome/BUILD.gn
[modify] https://crrev.com/58f1f45cb86735c30e2787358cd3a0827fc8cde4/chrome/chrome_dll_bundle.gypi

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2ff5b4cd942039905c9e26a5abdb9607e1338329

commit 2ff5b4cd942039905c9e26a5abdb9607e1338329
Author: waffles <waffles@chromium.org>
Date: Tue Jun 21 21:38:10 2016

Allow DCI to pick up contents from Internet Plug-Ins on OS X.
On other platforms, this should have no effect, since
DIR_INTERNAL_PLUGINS == DIR_COMPONENTS.

BUG= 601928 

Review-Url: https://codereview.chromium.org/2085583005
Cr-Commit-Position: refs/heads/master@{#401114}

[modify] https://crrev.com/2ff5b4cd942039905c9e26a5abdb9607e1338329/chrome/app/chrome_main_delegate.cc
[modify] https://crrev.com/2ff5b4cd942039905c9e26a5abdb9607e1338329/chrome/test/base/chrome_unit_test_suite.cc
[modify] https://crrev.com/2ff5b4cd942039905c9e26a5abdb9607e1338329/components/component_updater/component_updater_paths.cc
[modify] https://crrev.com/2ff5b4cd942039905c9e26a5abdb9607e1338329/components/component_updater/component_updater_paths.h
[modify] https://crrev.com/2ff5b4cd942039905c9e26a5abdb9607e1338329/components/component_updater/default_component_installer.cc
[modify] https://crrev.com/2ff5b4cd942039905c9e26a5abdb9607e1338329/components/component_updater/default_component_installer.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5a2538963cbd28c53ed0f4befc24bd9b4d99f77c

commit 5a2538963cbd28c53ed0f4befc24bd9b4d99f77c
Author: waffles <waffles@chromium.org>
Date: Fri Jun 24 21:21:09 2016

Refactor flash component installer to use DefaultComponentInstaller.
This enables it to use differential updates.

BUG= 601928 

Review-Url: https://codereview.chromium.org/2041573002
Cr-Commit-Position: refs/heads/master@{#401973}

[modify] https://crrev.com/5a2538963cbd28c53ed0f4befc24bd9b4d99f77c/chrome/browser/component_updater/pepper_flash_component_installer.cc
[modify] https://crrev.com/5a2538963cbd28c53ed0f4befc24bd9b4d99f77c/chrome/browser/component_updater/pepper_flash_component_installer.h

Fixed. Removed RVG since we didn't wind up discussing data on this bug.

Server-side implementation is also done, modulo a small CL and the issue that we don't want to serve diff updates to pre-53 Chromes for this component.

Observed a Flash differential update from .192 to .200 on M53 tip-of-tree Linux build:

<event eventtype="3" eventresult="1" diffresult="1" nextfp="1.5c6d5f5fcfe7117334ce93f178bcd7c8a2eefe8fd69cf7c01156189509eb1a2e"/><event eventtype="14" eventresult="1" downloader="direct" url="http://storage.googleapis.com/update-delta/mimojjlkmoijpicakmndhoigimigcmbb/22.0.0.200/22.0.0.192/c6d467b17780c2993e6a3851aebd3ed1eb04988d361b4de44812307f956337f1.crxd" downloaded="700955" total="700955" download_time_ms="381"/>

Diff size was 700955 bytes, full size is 6897379 bytes, achieved 89.8% space savings.

That's awesome!