Deduplicate layout test suite configurations.

webkit_layout_tests_isolated_scripts was identical to
chromium_webkit_isolated_scripts except for the configured shard
count.

Bug: 910859
Change-Id: Ie014793403154978e08e47cebaf04631a45a1e24
Reviewed-on: https://chromium-review.googlesource.com/c/1359032Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Reviewed-by: Ben Pastene <bpastene@chromium.org>
Commit-Queue: Philip Rogers <pdr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#613339}

testing/buildbot/chromium.fyi.json

@@ -2209,7 +2209,7 @@
             }
           ],
           "hard_timeout": 900,
-          "shards": 15
+          "shards": 12
         }
       }
     ]
@@ -2238,7 +2238,7 @@
             }
           ],
           "hard_timeout": 900,
-          "shards": 15
+          "shards": 12
         }
       }
     ]
@@ -2268,7 +2268,7 @@
           ],
           "hard_timeout": 900,
           "priority_adjustment": 30,
-          "shards": 15
+          "shards": 12
         }
       }
     ]
@@ -4300,7 +4300,8 @@
         "name": "webkit_layout_tests",
         "results_handler": "layout tests",
         "swarming": {
-          "can_use_on_swarming_builders": true
+          "can_use_on_swarming_builders": true,
+          "shards": 12
         }
       }
     ]

testing/buildbot/test_suite_exceptions.pyl

@@ -1381,25 +1381,16 @@
           '--additional-driver-flag=--enable-blink-features=LayoutNG',
           '--additional-driver-flag=--enable-slimming-paint-v175',
         ],
-        'swarming': {
-          'shards': 15,
-        },
       },
       'WebKit Linux root_layer_scrolls Dummy Builder': {
         'args': [
           '--additional-driver-flag=--root-layer-scrolls',
         ],
-        'swarming': {
-          'shards': 15,
-        },
       },
       'WebKit Linux slimming_paint_v2 Dummy Builder': {
         'args': [
           '--additional-driver-flag=--enable-slimming-paint-v2',
         ],
-        'swarming': {
-          'shards': 15,
-        },
       },
       # chromium.linux
       'Linux Tests': {

testing/buildbot/test_suites.pyl

@@ -2366,28 +2366,6 @@
       'vr_pixeltests': {},
     },
 
-    # TODO(kbr): figure out a nicer way to add additional command line arguments
-    # to a base test suite (or across multiple test suites, per builder) than just
-    # adding them to test_suite_exceptions.pyl.
-    'webkit_layout_tests_isolated_scripts': {
-      'webkit_layout_tests': {
-        # layout test failures are retried 3 times when '--test-list' is not
-        # passed, but 0 times when '--test-list' is passed. We want to always
-        # retry 3 times, so we explicitly specify it.
-        'args': [
-          '--num-retries=3',
-        ],
-        'isolate_name': 'webkit_layout_tests_exparchive',
-        'merge': {
-          'args': [
-            '--verbose'
-          ],
-          'script': '//third_party/blink/tools/merge_web_test_results.py',
-        },
-        'results_handler': 'layout tests',
-      },
-    },
-
     # TODO(crbug.com/888429): Port remaining WebRTC tests to swarming.
     'webrtc_chromium_baremetal_gtests': {
       # Run capture unittests as well since our bots have real webcams.

testing/buildbot/waterfalls.pyl

@@ -1252,7 +1252,7 @@
         },
         'test_suites': {
           'gtest_tests': 'layout_ng_gtests',
-          'isolated_scripts': 'webkit_layout_tests_isolated_scripts',
+          'isolated_scripts': 'chromium_webkit_isolated_scripts',
         },
       },
       'WebKit Linux root_layer_scrolls Dummy Builder': {
@@ -1265,7 +1265,7 @@
           'hard_timeout': 900,
         },
         'test_suites': {
-          'isolated_scripts': 'webkit_layout_tests_isolated_scripts',
+          'isolated_scripts': 'chromium_webkit_isolated_scripts',
         },
       },
       'WebKit Linux slimming_paint_v2 Dummy Builder': {
@@ -1283,7 +1283,7 @@
           'priority_adjustment': 30,
         },
         'test_suites': {
-          'isolated_scripts': 'webkit_layout_tests_isolated_scripts',
+          'isolated_scripts': 'chromium_webkit_isolated_scripts',
         },
       },
       'Win 10 Fast Ring': {
@@ -1444,7 +1444,7 @@
       },
       'linux-blink-gen-property-trees': {
         'test_suites': {
-          'isolated_scripts': 'webkit_layout_tests_isolated_scripts',
+          'isolated_scripts': 'chromium_webkit_isolated_scripts',
         },
       },
       'linux-blink-heap-incremental-marking': {