Roll chromium_revision 1728ddf..4623ce8 (370595:370665)

Change log: https://chromium.googlesource.com/chromium/src/+log/1728ddf..4623ce8
Full diff: https://chromium.googlesource.com/chromium/src/+/1728ddf..4623ce8

Changed dependencies:
* src/third_party/boringssl/src: https://boringssl.googlesource.com/boringssl.git/+log/afe57cb..6c22f54
DEPS diff: https://chromium.googlesource.com/chromium/src/+/1728ddf..4623ce8/DEPS

No update to Clang.

TBR=

Review URL: https://codereview.webrtc.org/1617693002

Cr-Commit-Position: refs/heads/master@{#11335}
diff --git a/DEPS b/DEPS
index 4ba5e68..810e711 100644
--- a/DEPS
+++ b/DEPS
@@ -6,7 +6,7 @@
 vars = {
   'extra_gyp_flag': '-Dextra_gyp_flag=0',
   'chromium_git': 'https://chromium.googlesource.com',
-  'chromium_revision': '1728ddff937e0bfc42bba8f2b23a61f0ed99ed85',
+  'chromium_revision': '4623ce800b2050be83f307f351fb5a8addf3e676',
 }
 
 # NOTE: Prefer revision numbers to tags for svn deps. Use http rather than