[tabmanager] Do not set the PageLifecycle run-time enabled feature in tests.

This feature no longer exists and is not needed for tests.

Change-Id: I5f5bb7e6ae3a4b90c0ea5638737e13eb4b20c5c6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2305513Reviewed-by: Sébastien Marchand <sebmarchand@chromium.org>
Commit-Queue: François Doray <fdoray@chromium.org>
Cr-Commit-Position: refs/heads/master@{#789936}

chrome/browser/resource_coordinator/tab_manager_browsertest.cc

@@ -62,7 +62,6 @@ namespace resource_coordinator {
 
 namespace {
 
-constexpr char kBlinkPageLifecycleFeature[] = "PageLifecycle";
 constexpr base::TimeDelta kShortDelay = base::TimeDelta::FromSeconds(1);
 
 bool ObserveNavEntryCommitted(const GURL& expected_url,
@@ -153,11 +152,6 @@ class TabManagerTest : public InProcessBrowserTest {
     test_clock_.Advance(kShortDelay);
   }
 
-  void SetUpCommandLine(base::CommandLine* command_line) override {
-    command_line->AppendSwitchASCII(switches::kEnableBlinkFeatures,
-                                    kBlinkPageLifecycleFeature);
-  }
-
   void SetUpOnMainThread() override {
     InProcessBrowserTest::SetUpOnMainThread();
     host_resolver()->AddRule("*", "127.0.0.1");