Run angle_end2end_tests standalone on the bots.

Example run time improvements, sum of all shards:

Intel GPU on Windows: 10m 45s -> 3m 46s
NVIDIA GPU on Windows: 13m 5s -> 4m 7s
ATI GPU on Windows: 17m 23s -> 2m 33s
ATI GPU on Mac Retina: 3m 20s -> 1m 0s
Intel GPU on Mac: 3m 29s -> 1m 30s
NVIDIA GPU on Mac Retina: 11m 41s -> 6m 7s
Intel GPU on Linux: 5m 55s -> 1m 5s
NVIDIA GPU on Linux: 26m 40s -> 6m 3s

Bug: angleproject:5124
Change-Id: Iccbc0646b215d43f4f59c6af98fc3e1a80cb245d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2412785Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816566}

testing/buildbot/gn_isolate_map.pyl

@@ -1541,10 +1541,15 @@
     "label": "//sql:sql_unittests",
     "type": "console_test_launcher",
   },
+  "standalone_angle_end2end_tests": {
+    "label": "//third_party/angle/src/tests:standalone_angle_end2end_tests",
+    "script": "//third_party/angle/scripts/run_gtest_angle_test.py",
+    "type": "script",
+  },
   "standalone_angle_unittests": {
     "label": "//third_party/angle/src/tests:standalone_angle_unittests",
-    "type": "script",
     "script": "//third_party/angle/scripts/run_gtest_angle_test.py",
+    "type": "script",
   },
   "storage_unittests": {
     "label": "//storage:storage_unittests",

testing/buildbot/test_suites.pyl

@@ -1951,25 +1951,29 @@
     },
 
     'gpu_angle_end2end_gtests': {
-      'angle_end2end_tests': {
+      'standalone_angle_end2end_tests': {
         'android_args': [
-          '--shard-timeout=180'
-        ],
-        'desktop_args': [
-          '--use-gpu-in-tests',
+          '--shard-timeout=180',
+          '-v',
         ],
+        'android_swarming': {
+          'shards': 4,
+        },
         'args': [
-          # ANGLE test retries deliberately disabled to prevent flakiness.
-          # http://crbug.com/669196
-          '--test-launcher-retry-limit=0',
-          '--test-launcher-batch-limit=256',
+          'standalone_angle_end2end_tests',
           '--gtest_filter=-*Vulkan_SwiftShader*',
         ],
-        'linux_args': ['--no-xvfb'],
-        'should_retry_with_patch': False,
+        'desktop_args': [
+          '--bot-mode',
+        ],
+        # Linux has issues with creating too many windows at once.
+        'linux_args': [
+          '--max-processes=4',
+        ],
         'swarming': {
-          'shards': 4,
+          'shards': 2,
         },
+        'use_isolated_scripts_api': True,
       },
     },
 
@@ -4097,15 +4101,16 @@
           '--test-launcher-retry-limit=0',
         ],
       },
-      'angle_end2end_tests': {
+      'standalone_angle_end2end_tests': {
         'args': [
+          'standalone_angle_end2end_tests',
+          '--bot-mode',
           '--gtest_filter=*Vulkan_SwiftShader*',
-          '--test-launcher-batch-limit=512',
-          '--test-launcher-retry-limit=0',
         ],
-        'swarming': {
-          'shards': 2,
-        },
+        'linux_args': [
+          '--xvfb',
+        ],
+        'use_isolated_scripts_api': True,
       },
     },