Reland: Remove "needkey" event and add its replacement, "encrypted".

Source/modules/modules.gypi

Index: Source/modules/modules.gypi
diff --git a/Source/modules/modules.gypi b/Source/modules/modules.gypi
index 12f1562f571afff1072cfa7a7f754e4ebb78bafb..cf40a16548eda68f70dfa5a8bd0e646bfde9f26e 100644
--- a/Source/modules/modules.gypi
+++ b/Source/modules/modules.gypi
@@ -32,8 +32,8 @@
       'device_orientation/DeviceRotationRate.idl',
       'encoding/TextDecoder.idl',
       'encoding/TextEncoder.idl',
+      'encryptedmedia/MediaEncryptedEvent.idl',
       'encryptedmedia/MediaKeyMessageEvent.idl',
-      'encryptedmedia/MediaKeyNeededEvent.idl',
       'encryptedmedia/MediaKeySession.idl',
       'encryptedmedia/MediaKeys.idl',
       'filesystem/DOMFileSystem.idl',
@@ -260,8 +260,8 @@
       'device_light/DeviceLightEvent.idl',
       'device_orientation/DeviceMotionEvent.idl',
       'device_orientation/DeviceOrientationEvent.idl',
+      'encryptedmedia/MediaEncryptedEvent.idl',
       'encryptedmedia/MediaKeyMessageEvent.idl',
-      'encryptedmedia/MediaKeyNeededEvent.idl',
       'gamepad/GamepadEvent.idl',
       'geofencing/GeofencingEvent.idl',
       'indexeddb/IDBVersionChangeEvent.idl',
@@ -409,10 +409,10 @@
       'encoding/TextEncoder.h',
       'encryptedmedia/HTMLMediaElementEncryptedMedia.cpp',
       'encryptedmedia/HTMLMediaElementEncryptedMedia.h',
+      'encryptedmedia/MediaEncryptedEvent.cpp',
+      'encryptedmedia/MediaEncryptedEvent.h',
       'encryptedmedia/MediaKeyMessageEvent.cpp',
       'encryptedmedia/MediaKeyMessageEvent.h',
-      'encryptedmedia/MediaKeyNeededEvent.cpp',
-      'encryptedmedia/MediaKeyNeededEvent.h',
       'encryptedmedia/MediaKeySession.cpp',
       'encryptedmedia/MediaKeySession.h',
       'encryptedmedia/MediaKeys.cpp',