Fix embedder_->EndFrame() not called in case of DrawLastLayerTree()

[eggfly]

It fixes this video flicker bug:

• [Android] Rendering video with TextureWidget in front of a PlatformView causes flicker flutter#94612

The root cause is EndFrame() is not called in case of DrawLastLayerTree() when reusing previous layer tree.
The detail context is in the issue 😁 flutter/flutter#94612

file_v2_37c4c961-3b3d-4d18-8838-ab9d66e6262g_videoCacheDE7C4520-DC0E-41F9-9EDE-3F5502F1B64B.origin.model.video.path.mov.mp4

And after this fix, the app works correctly:

ok.mp4

Pre-launch Checklist

• I read the [Contributor Guide] and followed the process outlined there for submitting PRs.
• I read the [Tree Hygiene] wiki page, which explains my responsibilities.
• I read and followed the [Flutter Style Guide] and the [C++, Objective-C, Java style guides].
• I listed at least one issue that this PR fixes in the description above.
• I added new tests to check the change I am making or feature I am adding, or Hixie said the PR is test-exempt. See [testing the engine] for instructions on
  writing and running engine tests.
• I updated/added relevant documentation (doc comments with ///).
• I signed the [CLA].
• All existing and new tests are passing.

[iskakaushik]

LGTM

[eggfly]

Also fix:

• Is the duplicate libflutter.so in android-x86/artifacts.zip redundant? flutter#94667