[testing] Enable end2end experiments for Windows continuous integration jobs (#32567)

Co-authored-by: drfloob <drfloob@users.noreply.github.com>

bazel/experiments.bzl

@@ -21,14 +21,10 @@ EXPERIMENTS = {
         "dbg": {
         },
         "off": {
-            "cancel_ares_query_test": [
-                "event_engine_dns",
-            ],
             "census_test": [
                 "transport_supplies_client_latency",
             ],
             "core_end2end_test": [
-                "event_engine_client",
                 "event_engine_listener",
                 "promise_based_client_call",
                 "promise_based_server_call",
@@ -42,9 +38,6 @@ EXPERIMENTS = {
                 "tcp_frame_size_tuning",
                 "tcp_rcv_lowat",
             ],
-            "event_engine_client_test": [
-                "event_engine_client",
-            ],
             "event_engine_listener_test": [
                 "event_engine_listener",
             ],
@@ -59,9 +52,6 @@ EXPERIMENTS = {
             "logging_test": [
                 "promise_based_server_call",
             ],
-            "resolver_component_tests_runner_invoker": [
-                "event_engine_dns",
-            ],
             "resource_quota_test": [
                 "free_large_allocator",
                 "memory_pressure_controller",
@@ -78,14 +68,10 @@ EXPERIMENTS = {
         "dbg": {
         },
         "off": {
-            "cancel_ares_query_test": [
-                "event_engine_dns",
-            ],
             "census_test": [
                 "transport_supplies_client_latency",
             ],
             "core_end2end_test": [
-                "event_engine_client",
                 "event_engine_listener",
                 "promise_based_client_call",
                 "promise_based_server_call",
@@ -99,9 +85,6 @@ EXPERIMENTS = {
                 "tcp_frame_size_tuning",
                 "tcp_rcv_lowat",
             ],
-            "event_engine_client_test": [
-                "event_engine_client",
-            ],
             "event_engine_listener_test": [
                 "event_engine_listener",
             ],
@@ -116,9 +99,6 @@ EXPERIMENTS = {
             "logging_test": [
                 "promise_based_server_call",
             ],
-            "resolver_component_tests_runner_invoker": [
-                "event_engine_dns",
-            ],
             "resource_quota_test": [
                 "free_large_allocator",
                 "memory_pressure_controller",

bazel/grpc_build_system.bzl

@@ -394,8 +394,6 @@ def expand_tests(name, srcs, deps, tags, args, exclude_pollers, uses_polling, us
     must_have_tags = [
         # We don't run experiments on cmake builds
         "bazel_only",
-        # Nor on windows
-        "no_windows",
         # Nor on mac
         "no_mac",
         # Nor on arm64

src/core/lib/experiments/rollouts.yaml

@@ -47,7 +47,13 @@
 - name: unconstrained_max_quota_buffer_size
   default: false
 - name: event_engine_client
-  default: false
+  default:
+    # not tested on iOS at all
+    ios: broken
+    posix: false
+    # TODO(hork): resolve when the client end2end test flake rate reduces to
+    # a tolerable amount.
+    windows: broken
 - name: monitoring_experiment
   default: true
 - name: promise_based_client_call
@@ -65,7 +71,13 @@
 - name: trace_record_callops
   default: false
 - name: event_engine_dns
-  default: false
+  default:
+    # not tested on iOS at all
+    ios: broken
+    posix: false
+    # TODO(yijiem): resolve when the WindowsEventEngine DNS Resolver is 
+    # implemented
+    windows: broken
 - name: work_stealing
   default: false
 - name: client_privacy