For anyone looking at this bug, here is a design doc with mockups of what I want the UI for this to look like: https://docs.google.com/a/google.com/document/d/1-5CDWhSx_QOMuiHomF8YZqU25eUxnQJjKH3tv-caR64/edit?usp=sharing 

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra/+/ec9728015b8fa579fb6ab6634dfe50874ab8c37d

commit ec9728015b8fa579fb6ab6634dfe50874ab8c37d
Author: Tiff Zhang <zhangtiff@google.com>
Date: Wed Jun 07 22:05:24 2017

SoM: Add bulk annotation actions.

Bug:717713
Change-Id: I60f6dfe093b51d599779c624fdc50eb9b5db2703
Reviewed-on: https://chromium-review.googlesource.com/524026
Reviewed-by: Sean McCullough <seanmccullough@chromium.org>
Commit-Queue: Tiffany Zhang <zhangtiff@chromium.org>

[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-app/som-app.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-marked-element/som-marked-element.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-swarming-bots/som-swarming-bots.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/test/som-tree-status-test.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-rev-range/som-rev-range.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-alert-view/som-alert-view.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/test/som-annotations-test.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-examine/som-examine.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-app/som-app.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-drawer/som-drawer.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-annotations/som-annotations.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/test/som-alert-item-test.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-test-expectations/som-test-expectations.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-alert-item/som-alert-item.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-extension-trooper-failure/som-extension-trooper-failure.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-master-restarts/som-master-restarts.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-extension-trooper-failure/som-extension-trooper-failure.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-extension-build-failure/som-extension-build-failure.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/index.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-input-styles.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-tree-status/som-tree-status.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-extension-cros-failure/som-extension-cros-failure.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-annotations/som-annotations.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-bug-queue/som-bug-queue.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-header-styles.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-webkit-tests/som-webkit-tests.js
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-alert-view/som-alert-view.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-master-restarts/som-master-restarts.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/.clang-format
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-alert-item/som-alert-item.html
[modify] https://crrev.com/ec9728015b8fa579fb6ab6634dfe50874ab8c37d/go/src/infra/appengine/sheriff-o-matic/frontend/elements/som-settings/som-settings.js

The following revision refers to this bug:
  https://chrome-internal.googlesource.com/infra/puppet/+/10f8637e68e7474ccdc41e3d117697b515a21b28

commit 10f8637e68e7474ccdc41e3d117697b515a21b28
Author: Katie Thomas <katthomas@google.com>
Date: Thu Jun 08 17:54:46 2017

This is deployed. 

I just used this for the first time and it's great. Thanks :)