Using ToT (currently 0205c5d89896956f)

* Preconditions
- I'm building on Linux
- Building blink_tests target
- Using gyp
- Building with gcc and system's linker
- GYP_DEFINES=disable_nacl=1 disable_pnacl=1 fastbuild=1 dcheck_always_on=1 component=shared_library clang=0 linux_use_bundled_binutils=0 linux_use_bundled_gold=1 use_sysroot=0

* Link error:

obj/third_party/WebKit/Source/core/loader/webkit_unit_tests.ThreadableLoaderTest.o:ThreadableLoaderTest.cpp:function void WTF::HashTable<char const*, WTF::KeyValuePair<char const*, blink::Member<blink::Supplement<blink::WorkerGlobalScope> > >, WTF::KeyValuePairKeyExtractor, WTF::PtrHash<char const>, WTF::HashMapValueTraits<WTF::HashTraits<char const*>, WTF::HashTraits<blink::Member<blink::Supplement<blink::WorkerGlobalScope> > > >, WTF::HashTraits<char const*>, blink::HeapAllocator>::trace<blink::InlinedGlobalMarkingVisitor>(blink::InlinedGlobalMarkingVisitor): error: undefined reference to 'blink::WorkerGlobalScopePerformance::trace(blink::InlinedGlobalMarkingVisitor)'
obj/third_party/WebKit/Source/core/loader/webkit_unit_tests.ThreadableLoaderTest.o:ThreadableLoaderTest.cpp:function blink::WorkerGlobalScopePerformance::adjustAndMark(blink::Visitor*) const: error: undefined reference to 'blink::WorkerGlobalScopePerformance::trace(blink::InlinedGlobalMarkingVisitor)'
obj/third_party/WebKit/Source/core/loader/webkit_unit_tests.ThreadableLoaderTest.o:ThreadableLoaderTest.cpp:function blink::WorkerGlobalScopePerformance::adjustAndMark(blink::Visitor*) const: error: undefined reference to 'blink::WorkerGlobalScopePerformance::trace(blink::Visitor*)'
obj/third_party/WebKit/Source/core/loader/webkit_unit_tests.ThreadableLoaderTest.o:ThreadableLoaderTest.cpp:function blink::Supplementable<blink::WorkerGlobalScope>::trace(blink::Visitor*): error: undefined reference to 'blink::WorkerGlobalScopePerformance::trace(blink::Visitor*)'
obj/third_party/WebKit/Source/core/loader/webkit_unit_tests.ThreadableLoaderTest.o:ThreadableLoaderTest.cpp:function blink::Supplementable<blink::WorkerGlobalScope>::trace(blink::Visitor*): error: undefined reference to 'blink::WorkerGlobalScopePerformance::trace(blink::InlinedGlobalMarkingVisitor)'
collect2: error: ld returned 1 exit status