Control ES2015 'Tail call elimination' language feature via finch flag.

base/test/test_suite.cc

Index: base/test/test_suite.cc
diff --git a/base/test/test_suite.cc b/base/test/test_suite.cc
index 74bd9ddf7bd5bd238fb4997630c7dc5bdf51370b..985afb0e896d3f8519821a2371845dd721228317 100644
--- a/base/test/test_suite.cc
+++ b/base/test/test_suite.cc
@@ -11,7 +11,6 @@
 #include "base/command_line.h"
 #include "base/debug/debugger.h"
 #include "base/debug/stack_trace.h"
-#include "base/feature_list.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/i18n/icu_util.h"
@@ -224,15 +223,8 @@ int TestSuite::Run() {
   test_listener_ios::RegisterTestEndListener();
 #endif
 
-  // Set up a FeatureList instance, so that code using that API will not hit a
-  // an error that it's not set. Cleared by ClearInstanceForTesting() below.
-  base::FeatureList::SetInstance(make_scoped_ptr(new base::FeatureList));

[Igor Sheludko, 2016/03/29 21:18:20]

At this moment gin::IsolateHolder (and therefore FeatureList) is already
initialized and this call to SetInstance hits assertion failure.

-
   int result = RUN_ALL_TESTS();
 
-  // Clear the FeatureList that was registered above.
-  FeatureList::ClearInstanceForTesting();
-
 #if defined(OS_MACOSX)
   // This MUST happen before Shutdown() since Shutdown() tears down
   // objects (such as NotificationService::current()) that Cocoa