tvos: Fix VP9 header include path

[abhijeetk]

The include path for the VP9 hardware AV video sample buffer
builder header was incorrectly using the 'internal-starboard'
prefix. This change corrects the path to 'starboard' and ensures
the header is properly included in the build system when the
internal build flag is enabled. This resolves build failures
when the preprocessor cannot locate the header file.

Bug: 452554667

[github-actions]

🤖 Gemini Suggested Commit Message

---

tvos: Fix VP9 header include path

The include path for the VP9 hardware AV video sample buffer
builder header was incorrectly using the 'internal-starboard'
prefix. This change corrects the path to 'starboard' and ensures
the header is properly included in the build system when the
internal build flag is enabled. This resolves build failures
when the preprocessor cannot locate the header file.

Bug: 452554667

---

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[abhijeetk]

cc: @jkim-julie @Gyuyoung

[gemini-code-assist]

Code Review

This pull request corrects an incorrect include path for a VP9 header on tvOS, which was causing build failures. The change updates the import path in av_video_sample_buffer_builder.mm and adds the necessary VP9 source files to the build system in BUILD.gn under the is_internal_build flag. The changes are correct, targeted, and effectively resolve the described build issue. I have no further comments.

[rakuco]

Hmm, I understand where this is coming from, but without @fayev-g and @oxve figuring out bug 460479616 this will remain broken anyway, won't it? Doesn't it make more sense to update the references in the non-public repositor{y,ies} in the meantime?