Roll chromium_revision 3a90ecf..a6aefb7 (374096:374428)

Change log: https://chromium.googlesource.com/chromium/src/+log/3a90ecf..a6aefb7
Full diff: https://chromium.googlesource.com/chromium/src/+/3a90ecf..a6aefb7

Changed dependencies:
* src/third_party/yasm/source/patched-yasm: https://chromium.googlesource.com/chromium/deps/yasm/patched-yasm.git/+log/4671120..7da28c6
DEPS diff: https://chromium.googlesource.com/chromium/src/+/3a90ecf..a6aefb7/DEPS

No update to Clang.

TBR=

Review URL: https://codereview.webrtc.org/1681213002

Cr-Commit-Position: refs/heads/master@{#11542}
diff --git a/DEPS b/DEPS
index 05727fe..04fe20b 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': '3a90ecfeb74acfc47de7df8b531ef30aa743f296',
+  'chromium_revision': 'a6aefb78f61d48f1b7d836013c99ce5dfd579a39',
 }
 
 # NOTE: Use http rather than https; the latter can cause problems for users