Remove NetDelayableH2AndQuicRequests from fieldtrial_testing_config

This CL removes "NetDelayableH2AndQuicRequests" from
fieldtrial_testing_config.json. The feature is disabled by default, and
we are disabling it on perf bots now - otherwise it may prevent us from
launching RendererSideResourceScheduler.

Bug: 785770, 794073
Change-Id: Ib65fbc5989295537f649fb5211606196efc52416
Reviewed-on: https://chromium-review.googlesource.com/901145Reviewed-by: Josh Karlin <jkarlin@chromium.org>
Reviewed-by: Jesse Doherty <jwd@chromium.org>
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534866}

testing/variations/fieldtrial_testing_config.json

@@ -2192,49 +2192,6 @@
             ]
         }
     ],
-    "NetDelayableH2AndQuicRequests": [
-        {
-            "platforms": [
-                "win"
-            ],
-            "experiments": [
-                {
-                    "name": "Enabled3",
-                    "enable_features": [
-                        "PrioritySupportedRequestsDelayable"
-                    ]
-                }
-            ]
-        },
-        {
-            "platforms": [
-                "mac"
-            ],
-            "experiments": [
-                {
-                    "name": "EnabledHead3",
-                    "enable_features": [
-                        "HeadPriorityRequestsDelayable"
-                    ]
-                }
-            ]
-        },
-        {
-            "platforms": [
-                "chromeos",
-                "linux",
-                "android"
-            ],
-            "experiments": [
-                {
-                    "name": "Yielding3",
-                    "enable_features": [
-                        "NetworkSchedulerYielding"
-                    ]
-                }
-            ]
-        }
-    ],
     "NetworkQualityEstimator": [
         {
             "platforms": [