DummySurface depends on EXT_protected_surface but doesn't check for support

[rtray]

This is a follow-up to issue 677. The DummySurface.java file was created in response to that issue (now closed).

EXT_protected_content doesn't explicitly support pbuffers and EglCreatePbufferSurface. That functionality was added as part of EXT_protected_surface.

The SECURE_SUPPORTED boolean should check for:
SECURE_SUPPORTED = extensions.contains("EGL_EXT_protected_content") && extensions.contains("EGL_EXT_protected_surface");

Some devices, like Nvidia Shield TV, support EXT_protected_content but not yet EXT_protected_surface. The DummySurface initInternal routine asserts.

Alternatives to using a PbufferSurface would be a temporary Window or Pixmap or make use of https://www.khronos.org/registry/EGL/extensions/KHR/EGL_KHR_surfaceless_context.txt

The issue can be reproduced while running the Google GTS (Google Mobile Services Test Suite) version 5.0_r2. The gts_tradefed command for the specific failure is:
run gts -m GtsExoPlayerTestCases -t com.google.android.exoplayer.gts.DashTest#testWidevineH264AdaptiveWithRendererDisabling --logcat-on-failure

The DummySurface code doesn't appear to be hit on the current release build for the Nvidia Shield TV. But an pre-release beta of the next version (for Android O) does and the asserts cause GTS to fail.

I cannot tell what version of ExoPlayer GTS-5.0R2 uses.

[davebytes]

Just wanted to add that on the same pre-release OS, this is also causing error dialogs in seemingly normal use cases of at least one major streaming media app.

[andrewlewis]

@rtray Thanks for the information. Does the pre-release Nvidia Shield TV build support EGL_KHR_surfaceless_context?

There are some devices where this code works as-is, despite EGL_EXT_protected_surface not being supported, so I'm hesitant just to add the extra check. I followed up internally and the best option seems to be to use surfaceless contexts where possible, with a fallback to the existing approach if it's unavailable (apparently it is not yet widely supported). Does that sound reasonable?

[rtray]

Thanks for the update Andrew.

Yes, the current nvidia devices (shield tablet and tv) support EGL_KHR_surfaceless_context with the current releases. The future releases will continue to support it.
Using surfaceless contexts with protected content as a backup sounds fine to me.

[ojw28]

@rtray - Are you on the buganizer issue about this topic [id: 70485423]? If not, please could you take a look? If you don't have access and don't know how to get it, let me know. Thanks!

[rtray]

@ojw28 - Sorry for the delay in response. I don't have access to buganizer and topic 70485423. If this is still relevant, I'll take a look if you send me a link or a clue how to get access.