Roll chromium_revision a56f16d1e1..29056bf821 (386317:386325)

Change log: https://chromium.googlesource.com/chromium/src/+log/a56f16d1e1..29056bf821
Full diff: https://chromium.googlesource.com/chromium/src/+/a56f16d1e1..29056bf821

No dependencies changed.
No update to Clang.

TBR=

Review URL: https://codereview.webrtc.org/1873083002

Cr-Commit-Position: refs/heads/master@{#12306}
diff --git a/DEPS b/DEPS
index 6ef6ab2..a19f5d1 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': 'a56f16d1e111284a092d28ff79963302fd092e6a',
+  'chromium_revision': '29056bf8210713af6d20b96c935e4d9de2f2a3a3',
 }
 
 # NOTE: Use http rather than https; the latter can cause problems for users