Revert of Blink Animation: Extend Animation's GC lifetime if it has a finish promise.

third_party/WebKit/Source/core/animation/Animation.cpp

Index: third_party/WebKit/Source/core/animation/Animation.cpp
diff --git a/third_party/WebKit/Source/core/animation/Animation.cpp b/third_party/WebKit/Source/core/animation/Animation.cpp
index 5de8b9515a3fa10bab9c8bbb1d4da1e8f7a39b83..8b9f2414f1bbeba0c50e8c9ef1c391e036445a92 100644
--- a/third_party/WebKit/Source/core/animation/Animation.cpp
+++ b/third_party/WebKit/Source/core/animation/Animation.cpp
@@ -650,11 +650,7 @@
 }
 
 bool Animation::hasPendingActivity() const {
-  bool hasPendingPromise =
-      m_finishedPromise &&
-      m_finishedPromise->getState() == ScriptPromisePropertyBase::Pending;
-
-  return m_pendingFinishedEvent || hasPendingPromise ||
+  return m_pendingFinishedEvent ||
          (!m_finished && hasEventListeners(EventTypeNames::finish));
 }