Make EventInterfaces.in build step not depend on bindings generation

Source/modules/modules.gypi

Index: Source/modules/modules.gypi
diff --git a/Source/modules/modules.gypi b/Source/modules/modules.gypi
index 9f78638e1a3dbb753c8461b14a23711127d26415..2d15b028a28c280cc70a6dcaa4327b80948bbe36 100644
--- a/Source/modules/modules.gypi
+++ b/Source/modules/modules.gypi
@@ -226,6 +226,31 @@
       'webdatabase/WorkerGlobalScopeWebDatabase.idl',
       'webmidi/NavigatorWebMIDI.idl',
     ],
+    # interfaces that inherit from Event
+    'modules_event_idl_files': [
+      'device_orientation/DeviceMotionEvent.idl',
+      'device_orientation/DeviceOrientationEvent.idl',
+      'encryptedmedia/MediaKeyMessageEvent.idl',
+      'encryptedmedia/MediaKeyNeededEvent.idl',
+      'gamepad/GamepadEvent.idl',
+      'indexeddb/IDBVersionChangeEvent.idl',
+      'mediastream/MediaStreamEvent.idl',
+      'mediastream/MediaStreamTrackEvent.idl',
+      'mediastream/RTCDTMFToneChangeEvent.idl',
+      'mediastream/RTCDataChannelEvent.idl',
+      'mediastream/RTCIceCandidateEvent.idl',
+      'serviceworkers/FetchEvent.idl',
+      'serviceworkers/InstallEvent.idl',
+      'serviceworkers/InstallPhaseEvent.idl',
+      'speech/SpeechRecognitionError.idl',
+      'speech/SpeechRecognitionEvent.idl',
+      'speech/SpeechSynthesisEvent.idl',
+      'webaudio/AudioProcessingEvent.idl',
+      'webaudio/OfflineAudioCompletionEvent.idl',
+      'webmidi/MIDIConnectionEvent.idl',
+      'webmidi/MIDIMessageEvent.idl',
+      'websockets/CloseEvent.idl',
+    ],
     'modules_files': [
       '<@(extra_blink_module_files)',
       'battery/BatteryManager.cpp',