GitLab

* Disable v1 signatures for Monochrome
* Disable v3 signatures always
* Adds timestamps for profiling (behind APKBUILDER_DEBUG)

Signing debug Monochrome.apk goes from 10 seconds to 3 seconds.

Here's an after breakdown from my machine:
I 59413      9 Started (apkbuilder.py)
D 59413     29 Adding AndroidManifest.xml
D 59413     33 Adding assets/
D 59413    360 Adding classes.dex
D 59413   1713 Adding lib/
D 59413   2107 Adding res/
D 59413   2286 Adding Java resources
D 59413   2294 Running zipalign
D 59413   2614 Signing apk
I 59413   7513 Job's done (apkbuilder.py)

Bug: 1036740
Change-Id: Ic12f52e5e3bd79ca057513cc2ae3d1c344d9858a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1980310Reviewed-by: Peter Wen <wnwen@chromium.org>
Commit-Queue: Peter Wen <wnwen@chromium.org>
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#728514}