See https://github.com/flutter/engine/blob/master/shell/platform/android/platform_view_android.cc#L77-L78

  FML_CHECK(android_context_ && android_context_->IsValid())
      << "Could not create an Android context.";

The android_context_->IsValid() always returns true. Inconsistent with expectations if AndroidContextGL can not be created.

android_context.h:
https://github.com/flutter/engine/blob/master/shell/platform/android/context/android_context.h#L29
android_context_gl.h:
https://github.com/flutter/engine/blob/master/shell/platform/android/android_context_gl.h#L106

It also can be found in latest release branch (1.22.x).