Remove LocalFrameLifecycleObserver::willDetachFrameHost()

third_party/WebKit/Source/core/core.gypi

 {
     'includes': [
         'core_generated.gypi',
     ],
     'variables': {
         # Files for which bindings (.cpp and .h files) will be generated
         'core_idl_files': [
             'animation/KeyframeEffect.idl',
             'animation/EffectModel.idl',
             'animation/AnimationEffectReadOnly.idl',
@@ skipping 1748 matching lines @@
             'frame/HostsUsingFeatures.cpp',
             'frame/HostsUsingFeatures.h',
             'frame/ImageBitmap.cpp',
             'frame/ImageBitmap.h',
             'frame/LayoutSubtreeRootList.cpp',
             'frame/LayoutSubtreeRootList.h',
             'frame/LocalDOMWindow.cpp',
             'frame/LocalDOMWindow.h',
             'frame/LocalFrame.cpp',
             'frame/LocalFrame.h',
-            'frame/LocalFrameLifecycleNotifier.cpp',
             'frame/LocalFrameLifecycleNotifier.h',
             'frame/LocalFrameLifecycleObserver.h',
             'frame/Location.cpp',
             'frame/Location.h',
             'frame/Navigator.cpp',
             'frame/Navigator.h',
             'frame/NavigatorCPU.cpp',
             'frame/NavigatorCPU.h',
             'frame/NavigatorID.cpp',
             'frame/NavigatorID.h',
@@ skipping 2426 matching lines @@
             'testing/PrivateScriptTestTest.cpp',
             'timing/MemoryInfoTest.cpp',
             'timing/PerformanceBaseTest.cpp',
             'timing/PerformanceObserverTest.cpp',
             'workers/WorkerThreadTest.cpp',
             'workers/WorkerThreadTestHelper.h',
             'xml/parser/SharedBufferReaderTest.cpp',
         ],
     }
 }