Add config and testing changes for accessibility blink try builder

This adds configs for a manually-triggered trybot that runs release
blink_web_tests with --force-renderer-accessibility, in order to start
stabilizing serialization/deserialization code for all the content
tested by the entire web_tests suite.

See corresponding tools/build cl landed here: crrev.com/c/2454398

Bug: 1135251
Change-Id: Ic9db4673a3bf580225864f1aa6b1da6a6e682793
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2453446Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Commit-Queue: Daniel Libby <dlibby@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#815296}

infra/config/generated/commit-queue.cfg

@@ -980,6 +980,10 @@ config_groups {
         location_regexp_exclude: ".+/[+]/docs/.+"
         location_regexp_exclude: ".+/[+]/infra/config/.+"
       }
+      builders {
+        name: "chromium/try/linux-blink-web-tests-force-accessibility-rel"
+        includable_only: true
+      }
       builders {
         name: "chromium/try/linux-chromeos-compile-dbg"
         location_regexp: ".*"

infra/config/generated/cr-buildbucket.cfg

@@ -21800,6 +21800,43 @@ buckets {
         }
       }
     }
+    builders {
+      name: "linux-blink-web-tests-force-accessibility-rel"
+      swarming_host: "chromium-swarm.appspot.com"
+      swarming_tags: "vpython:native-python-wrapper"
+      dimensions: "builderless:1"
+      dimensions: "cores:8"
+      dimensions: "cpu:x86-64"
+      dimensions: "os:Ubuntu-16.04"
+      dimensions: "pool:luci.chromium.try"
+      dimensions: "ssd:0"
+      exe {
+        cipd_package: "infra/recipe_bundles/chromium.googlesource.com/chromium/tools/build"
+        cipd_version: "refs/heads/master"
+        cmd: "recipes"
+      }
+      properties: "{\"$build/goma\":{\"enable_ats\":true,\"rpc_extra_params\":\"?prod\",\"server_host\":\"goma.chromium.org\",\"use_luci_auth\":true},\"$kitchen\":{\"devshell\":true,\"git_auth\":true},\"$recipe_engine/isolated\":{\"server\":\"https://isolateserver.appspot.com\"},\"builder_group\":\"tryserver.chromium.linux\",\"recipe\":\"chromium_trybot\"}"
+      execution_timeout_secs: 14400
+      expiration_secs: 7200
+      caches {
+        name: "win_toolchain"
+        path: "win_toolchain"
+      }
+      build_numbers: YES
+      service_account: "chromium-try-builder@chops-service-accounts.iam.gserviceaccount.com"
+      task_template_canary_percentage {
+        value: 5
+      }
+      resultdb {
+        enable: true
+        bq_exports {
+          project: "luci-resultdb"
+          dataset: "chromium"
+          table: "try_test_results"
+          test_results {}
+        }
+      }
+    }
     builders {
       name: "linux-chromeos-compile-dbg"
       swarming_host: "chromium-swarm.appspot.com"

infra/config/generated/luci-milo.cfg

@@ -11419,6 +11419,9 @@ consoles {
   builders {
     name: "buildbucket/luci.chromium.try/linux-blink-rel"
   }
+  builders {
+    name: "buildbucket/luci.chromium.try/linux-blink-web-tests-force-accessibility-rel"
+  }
   builders {
     name: "buildbucket/luci.chromium.try/linux-chromeos-compile-dbg"
   }
@@ -12255,6 +12258,9 @@ consoles {
   builders {
     name: "buildbucket/luci.chromium.try/linux-blink-heap-verification-try"
   }
+  builders {
+    name: "buildbucket/luci.chromium.try/linux-blink-web-tests-force-accessibility-rel"
+  }
   builders {
     name: "buildbucket/luci.chromium.try/linux-clang-tidy-dbg"
   }

infra/config/subprojects/chromium/try.star

@@ -833,6 +833,10 @@ try_.chromium_linux_builder(
     name = "linux-blink-heap-verification-try",
 )
 
+try_.chromium_linux_builder(
+    name = "linux-blink-web-tests-force-accessibility-rel",
+)
+
 try_.chromium_linux_builder(
     name = "linux-clang-tidy-dbg",
     executable = "recipe:tricium_clang_tidy_wrapper",

testing/buildbot/test_suite_exceptions.pyl

@@ -370,6 +370,11 @@
           '--additional-driver-flag=--enable-features=BlinkHeapConcurrentMarking',
         ],
       },
+      'linux-blink-web-tests-force-accessibility-rel': {
+        'args': [
+          '--additional-driver-flag=--force-renderer-accessibility',
+        ],
+      },
       'linux-code-coverage': {
         'args': [
           '--additional-env-var=LLVM_PROFILE_FILE=${ISOLATED_OUTDIR}/profraw/default-%2m.profraw',

testing/buildbot/tryserver.chromium.linux.json

@@ -6,6 +6,42 @@
       "browser_tests"
     ]
   },
+  "linux-blink-web-tests-force-accessibility-rel": {
+    "additional_compile_targets": [
+      "blink_tests"
+    ],
+    "isolated_scripts": [
+      {
+        "args": [
+          "--num-retries=3",
+          "--additional-driver-flag=--force-renderer-accessibility"
+        ],
+        "isolate_name": "blink_web_tests",
+        "merge": {
+          "args": [
+            "--verbose"
+          ],
+          "script": "//third_party/blink/tools/merge_web_test_results.py"
+        },
+        "name": "blink_web_tests",
+        "resultdb": {
+          "enable": true
+        },
+        "results_handler": "layout tests",
+        "swarming": {
+          "can_use_on_swarming_builders": true,
+          "dimension_sets": [
+            {
+              "os": "Ubuntu-16.04"
+            }
+          ],
+          "service_account": "chromium-tester@chops-service-accounts.iam.gserviceaccount.com",
+          "shards": 12
+        },
+        "test_id_prefix": "ninja://:blink_web_tests/"
+      }
+    ]
+  },
   "linux-layout-tests-edit-ng": {
     "additional_compile_targets": [
       "blink_tests"

testing/buildbot/waterfalls.pyl

@@ -5798,6 +5798,17 @@
           'linux-xenial',
         ],
       },
+      'linux-blink-web-tests-force-accessibility-rel': {
+        'additional_compile_targets': [
+          'blink_tests',
+        ],
+        'mixins': [
+          'linux-xenial',
+        ],
+        'test_suites': {
+          'isolated_scripts': 'chromium_webkit_isolated_scripts',
+        },
+      },
       'linux-layout-tests-edit-ng': {
         'additional_compile_targets': [
           'blink_tests',

tools/mb/mb_config.pyl

@@ -961,6 +961,7 @@
       'linux_layout_tests_composite_after_paint': 'gpu_tests_release_trybot',
       'linux_layout_tests_layout_ng_disabled': 'release_trybot',
       'linux-layout-tests-edit-ng': 'release_trybot',
+      'linux-blink-web-tests-force-accessibility-rel': 'release_trybot',
       'linux-layout-tests-fragment-item': 'release_trybot',
       'linux_mojo': 'release_trybot',
       'linux_mojo_chromeos': 'chromeos_with_codecs_release_trybot',

tools/mb/mb_config_expectations/tryserver.chromium.linux.json

@@ -348,6 +348,15 @@
       "use_goma": true
     }
   },
+  "linux-blink-web-tests-force-accessibility-rel": {
+    "gn_args": {
+      "dcheck_always_on": true,
+      "is_component_build": false,
+      "is_debug": false,
+      "symbol_level": 1,
+      "use_goma": true
+    }
+  },
   "linux-clang-tidy-dbg": {
     "gn_args": {
       "is_component_build": true,