[jfx21u] RFR: 8313900: Possible NULL pointer access in NativeAudioSpectrum and NativeVideoBuffer

[Alexander Matveev]

This is clean backport of JDK-8313900.

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Commit messages:
 - Backport 9f180e20adc5bc8e6892d9672a414e8b7f614a20

Changes: https://git.openjdk.org/jfx21u/pull/7/files
 Webrev: https://webrevs.openjdk.org/?repo=jfx21u&pr=7&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8313900
  Stats: 13 lines in 2 files changed: 11 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jfx21u/pull/7.diff
  Fetch: git fetch https://git.openjdk.org/jfx21u.git pull/7/head:pull/7

PR: https://git.openjdk.org/jfx21u/pull/7