Rolling r8 and d8 to 1.6.1

Just rolling to stay current. Brings in some more binary size improvements.

Change-Id: If7fdcaace3cd96339c1304155f264f7c3d7361ba
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1617132
Commit-Queue: Sam Maier <smaier@chromium.org>
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Auto-Submit: Sam Maier <smaier@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#660940}

DEPS

@@ -1247,7 +1247,7 @@ deps = {
       'packages': [
           {
               'package': 'chromium/third_party/r8',
-              'version': '-hqyjKgjGWSfNsdcPJAnYNVOb96JOv0pJM82vtRo9M8C',
+              'version': 'jfE9VkwFvzhAgaBwY40d5HnUk_gcPl8H5vqsTQtb7DYC',
           },
       ],
       'condition': 'checkout_android',

third_party/r8/README.chromium

 Name: R8
 URL: https://r8.googlesource.com/r8
-Revision: 887271c359ed811656e4b116fb58d64fa9728e0a
-Version: 1.5.20-dev
+Revision: 3f76a8b25588c00095f8285e8f264d7dd0cab527
+Version: 1.6.1-dev
 License: BSD 3-Clause
 License File: NOT_SHIPPED
 Security Critical: no