Remove WorkerNosniff(Block|Warn) runtime features

The flags have been stable since Sep 2018[1][2].

1: https://crrev.com/bd8853574964974b80f539f21e887b9932b5ebab
2: https://crrev.com/4b736aaff87186c442a20dc5e6823d0fe087e101

Bug: 794548, 924024
Change-Id: Ifb45d0114a398c410fe6f717247fea25c3c0fbad
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1609026Reviewed-by: Mike West <mkwst@chromium.org>
Commit-Queue: Yutaka Hirano <yhirano@chromium.org>
Cr-Commit-Position: refs/heads/master@{#659011}

third_party/blink/renderer/platform/loader/allowed_by_nosniff.cc

@@ -11,7 +11,6 @@
 #include "third_party/blink/renderer/platform/loader/fetch/resource_response.h"
 #include "third_party/blink/renderer/platform/network/http_names.h"
 #include "third_party/blink/renderer/platform/network/mime/mime_type_registry.h"
-#include "third_party/blink/renderer/platform/runtime_enabled_features.h"
 #include "third_party/blink/renderer/platform/weborigin/security_origin.h"
 
 namespace blink {
@@ -121,12 +120,8 @@ bool AllowMimeTypeAsScript(const String& mime_type,
     counter = kTextXmlFeatures[same_origin][is_worker_global_scope];
   }
 
-  // Depending on RuntimeEnabledFeatures, we'll allow, allow-but-warn, or block
-  // these types when we're in a worker.
-  bool allow = mime_type_check_mode == MimeTypeCheck::kLax ||
-               !RuntimeEnabledFeatures::WorkerNosniffBlockEnabled();
-  warn = allow && mime_type_check_mode == MimeTypeCheck::kStrict &&
-         RuntimeEnabledFeatures::WorkerNosniffWarnEnabled();
+  bool allow = mime_type_check_mode == MimeTypeCheck::kLax;
+  warn = false;
   return allow;
 }
 

third_party/blink/renderer/platform/loader/allowed_by_nosniff_test.cc

@@ -12,7 +12,6 @@
 #include "third_party/blink/renderer/platform/loader/testing/mock_fetch_context.h"
 #include "third_party/blink/renderer/platform/loader/testing/test_loader_factory.h"
 #include "third_party/blink/renderer/platform/loader/testing/test_resource_fetcher_properties.h"
-#include "third_party/blink/renderer/platform/runtime_enabled_features.h"
 
 namespace blink {
 
@@ -115,31 +114,6 @@ TEST_F(AllowedByNosniffTest, AllowedOrNot) {
     ResourceResponse response(url);
     response.SetHttpHeaderField("Content-Type", testcase.mimetype);
 
-    // Nosniff 'legacy' setting: Both worker + non-worker obey the 'allowed'
-    // setting. Warnings for any blocked script.
-    RuntimeEnabledFeatures::SetWorkerNosniffBlockEnabled(false);
-    RuntimeEnabledFeatures::SetWorkerNosniffWarnEnabled(false);
-    EXPECT_CALL(*context, CountUsage(_)).Times(::testing::AnyNumber());
-    if (!testcase.allowed)
-      EXPECT_CALL(*logger, AddConsoleMessage(_, _, _));
-    EXPECT_EQ(testcase.allowed,
-              AllowedByNosniff::MimeTypeAsScript(*context, logger, response,
-                                                 MimeTypeCheck::kLax, false));
-    ::testing::Mock::VerifyAndClear(context);
-
-    EXPECT_CALL(*context, CountUsage(_)).Times(::testing::AnyNumber());
-    if (!testcase.allowed)
-      EXPECT_CALL(*logger, AddConsoleMessage(_, _, _));
-    EXPECT_EQ(testcase.allowed,
-              AllowedByNosniff::MimeTypeAsScript(
-                  *context, logger, response, MimeTypeCheck::kStrict, false));
-    ::testing::Mock::VerifyAndClear(context);
-
-    // Nosniff worker blocked: Workers follow the 'strict_allow' setting.
-    // Warnings for any blocked scripts.
-    RuntimeEnabledFeatures::SetWorkerNosniffBlockEnabled(true);
-    RuntimeEnabledFeatures::SetWorkerNosniffWarnEnabled(false);
-
     EXPECT_CALL(*context, CountUsage(_)).Times(::testing::AnyNumber());
     if (!testcase.allowed)
       EXPECT_CALL(*logger, AddConsoleMessage(_, _, _));
@@ -155,27 +129,6 @@ TEST_F(AllowedByNosniffTest, AllowedOrNot) {
               AllowedByNosniff::MimeTypeAsScript(
                   *context, logger, response, MimeTypeCheck::kStrict, false));
     ::testing::Mock::VerifyAndClear(context);
-
-    // Nosniff 'legacy', but with warnings. The allowed setting follows the
-    // 'allowed' setting, but the warnings follow the 'strict' setting.
-    RuntimeEnabledFeatures::SetWorkerNosniffBlockEnabled(false);
-    RuntimeEnabledFeatures::SetWorkerNosniffWarnEnabled(true);
-
-    EXPECT_CALL(*context, CountUsage(_)).Times(::testing::AnyNumber());
-    if (!testcase.allowed)
-      EXPECT_CALL(*logger, AddConsoleMessage(_, _, _));
-    EXPECT_EQ(testcase.allowed,
-              AllowedByNosniff::MimeTypeAsScript(*context, logger, response,
-                                                 MimeTypeCheck::kLax, false));
-    ::testing::Mock::VerifyAndClear(context);
-
-    EXPECT_CALL(*context, CountUsage(_)).Times(::testing::AnyNumber());
-    if (!testcase.strict_allowed)
-      EXPECT_CALL(*logger, AddConsoleMessage(_, _, _));
-    EXPECT_EQ(testcase.allowed,
-              AllowedByNosniff::MimeTypeAsScript(
-                  *context, logger, response, MimeTypeCheck::kStrict, false));
-    ::testing::Mock::VerifyAndClear(context);
   }
 }
 

third_party/blink/renderer/platform/runtime_enabled_features.json5

@@ -1620,15 +1620,6 @@
       name: "WebXRPlaneDetection",
       // depends_on: ["WebXR"],  // TODO(https://crbug.com/954679): uncomment once bug is fixed
     },
-    {
-      name: "WorkerNosniffBlock",
-      status: "stable",
-    },
-    {
-      name: "WorkerNosniffWarn",
-      status: "stable",
-      implied_by: ["WorkerNosniffBlock"],
-    },
     {
       name: "WorkerTaskQueue",
       status: "experimental"