Make Animator::Render skip

shell/common/animator.cc

@@ -179,9 +179,18 @@ void Animator::EndFrame() {
 void Animator::Render(int64_t view_id,
                       std::unique_ptr<flutter::LayerTree> layer_tree,
                       float device_pixel_ratio) {
+  // Animator::Render should be called between BeginFrame and EndFrame,
+  // which is indicated by frame_timings_recorder_ being non-null.
+  // This might happen on release build, and is guarded by PlatformDispatcher on
+  // debug build.
+  // TODO(dkwingsmt): We should change this skip into an assertion.
+  // https://github.com/flutter/flutter/issues/137073
+  if (frame_timings_recorder_ == nullptr) {
+    return;
+  }
+
   has_rendered_ = true;
 
-  FML_CHECK(frame_timings_recorder_ != nullptr);
   TRACE_EVENT_WITH_FRAME_NUMBER(frame_timings_recorder_, "flutter",
                                 "Animator::Render", /*flow_id_count=*/0,
                                 /*flow_ids=*/nullptr);

shell/common/animator.h

@@ -58,7 +58,7 @@ class Animator final {
   ///
   ///           This method must be called during a vsync callback, or
   ///           technically, between Animator::BeginFrame and Animator::EndFrame
-  ///           (both private methods).
+  ///           (both private methods). Otherwise, this call will be ignored.
   ///
   void Render(int64_t view_id,
               std::unique_ptr<flutter::LayerTree> layer_tree,