Let AutoplayUmaHelper listen to visibilitychange instead of unload

third_party/WebKit/Source/core/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/chromecast_build.gni")
 import("//build/toolchain/toolchain.gni")
 import("//build/config/ui.gni")
 import("//build/split_static_library.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 import("//third_party/WebKit/Source/bindings/bindings.gni")
@@ skipping 1131 matching lines @@
     "frame/LocalFrameTest.cpp",
     "frame/OriginsUsingFeaturesTest.cpp",
     "frame/RootFrameViewportTest.cpp",
     "frame/SubresourceIntegrityTest.cpp",
     "frame/UseCounterTest.cpp",
     "frame/csp/CSPDirectiveListTest.cpp",
     "frame/csp/CSPSourceTest.cpp",
     "frame/csp/ContentSecurityPolicyTest.cpp",
     "frame/csp/SourceListDirectiveTest.cpp",
     "html/AutoplayExperimentTest.cpp",
+    "html/AutoplayUmaHelperTest.cpp",
     "html/FormDataTest.cpp",
     "html/HTMLDimensionTest.cpp",
     "html/HTMLEmbedElementTest.cpp",
     "html/HTMLFormControlElementTest.cpp",
     "html/HTMLIFrameElementPermissionsTest.cpp",
     "html/HTMLIFrameElementTest.cpp",
     "html/HTMLImageElementTest.cpp",
     "html/HTMLInputElementTest.cpp",
     "html/HTMLLinkElementSizesAttributeTest.cpp",
     "html/HTMLOutputElementTest.cpp",
@@ skipping 154 matching lines @@
   sources = [
     "html/parser/HTMLPreloadScannerFuzzer.cpp",
     "html/parser/TextResourceDecoderForFuzzing.h",
   ]
   seed_corpus = "//third_party/WebKit/LayoutTests/fast/parser"
   deps = [
     ":core",
     "../platform:blink_fuzzer_test_support",
   ]
 }