Disable WebRTC-H264 for viz_content_browsertests on Win10 x64.

Pass --disable-features=WebRTC-H264WithOpenH264FFmpeg to
viz_content_browsertests on "chromium.win:Win10 Tests x64" similarly
to how it's being done for content_browsertests.

Tbr: [email protected]
Bug: 867536
Change-Id: Ib04e95a3b1dd94b29027f7cda26b5780e1a16a92
Reviewed-on: https://chromium-review.googlesource.com/1154141
Reviewed-by: Kenneth Russell <[email protected]>
Reviewed-by: Dirk Pranke <[email protected]>
Commit-Queue: Kenneth Russell <[email protected]>
Cr-Commit-Position: refs/heads/master@{#578901}
diff --git a/testing/buildbot/test_suite_exceptions.pyl b/testing/buildbot/test_suite_exceptions.pyl
index 6216055..97cc087 100644
--- a/testing/buildbot/test_suite_exceptions.pyl
+++ b/testing/buildbot/test_suite_exceptions.pyl
@@ -1358,6 +1358,13 @@
           'shards': 7,
         },
       },
+      # chromium.win
+      'Win10 Tests x64': {
+        # crbug.com/868082
+        'args': [
+          '--disable-features=WebRTC-H264WithOpenH264FFmpeg',
+        ],
+      },
     },
   },
   'viz_browser_tests': {