void
VRDisplayHost::SubmitFrame(VRLayerParent* aLayer, const int32_t& aInputFrameID,
                           PTextureParent* aTexture, const gfx::Rect& aLeftEyeRect,
                           const gfx::Rect& aRightEyeRect)
{
    // aInputFrameID is no longer controlled by content with the WebVR 1.1 API
    // update; however, we will later use this code to enable asynchronous
    // submission of multiple layers to be composited.  This will enable
    // us to build browser UX that remains responsive even when content does
    // not consistently submit frames.

    int32_t inputFrameID = aInputFrameID;
    if (inputFrameID == 0) {
        inputFrameID = mInputFrameID;
    }
    if (inputFrameID < 0) {
        // Sanity check to prevent invalid memory access on builds with assertions
        // disabled.
        inputFrameID = 0;
    }

    VRHMDSensorState sensorState = mLastSensorState[inputFrameID % kMaxLatencyFrames];
    // It is possible to get a cache miss on mLastSensorState if latency is
    // longer than kMaxLatencyFrames.  An optimization would be to find a frame
    // that is closer than the one selected with the modulus.
    // If we hit this; however, latency is already so high that the site is
    // un-viewable and a more accurate pose prediction is not likely to
    // compensate.

    TextureHost* th = TextureHost::AsTextureHost(aTexture);
    // WebVR doesn't use the compositor to compose the frame, so use
    // AutoLockTextureHostWithoutCompositor here.
    AutoLockTextureHostWithoutCompositor autoLock(th);
    if (autoLock.Failed()) {
        NS_WARNING("Failed to lock the VR layer texture");
        return;
    }

    CompositableTextureSourceRef source;
    if (!th->BindTextureSource(source)) {
        NS_WARNING("The TextureHost was successfully locked but can't provide a TextureSource");
        return;
    }
    MOZ_ASSERT(source);

    IntSize texSize = source->GetSize();

    TextureSourceD3D11* sourceD3D11 = source->AsSourceD3D11();
    if (!sourceD3D11) {
        NS_WARNING("WebVR support currently only implemented for D3D11");
        return;
    }

    SubmitFrame(sourceD3D11, texSize, sensorState, aLeftEyeRect, aRightEyeRect);
}
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void
VRDisplayHost::SubmitFrame(VRLayerParent* aLayer, PTextureParent* aTexture,
                           const gfx::Rect& aLeftEyeRect,
                           const gfx::Rect& aRightEyeRect)
{
  if ((mDisplayInfo.mGroupMask & aLayer->GetGroup()) == 0) {
    // Suppress layers hidden by the group mask
    return;
  }

  TextureHost* th = TextureHost::AsTextureHost(aTexture);
  // WebVR doesn't use the compositor to compose the frame, so use
  // AutoLockTextureHostWithoutCompositor here.
  AutoLockTextureHostWithoutCompositor autoLock(th);
  if (autoLock.Failed()) {
    NS_WARNING("Failed to lock the VR layer texture");
    return;
  }

  CompositableTextureSourceRef source;
  if (!th->BindTextureSource(source)) {
    NS_WARNING("The TextureHost was successfully locked but can't provide a TextureSource");
    return;
  }
  MOZ_ASSERT(source);

  IntSize texSize = source->GetSize();

  TextureSourceD3D11* sourceD3D11 = source->AsSourceD3D11();
  if (!sourceD3D11) {
    NS_WARNING("WebVR support currently only implemented for D3D11");
    return;
  }

  if (!SubmitFrame(sourceD3D11, texSize, aLeftEyeRect, aRightEyeRect)) {
    return;
  }

  /**
   * Trigger the next VSync immediately after we are successfully
   * submitting frames.  As SubmitFrame is responsible for throttling
   * the render loop, if we don't successfully call it, we shouldn't trigger
   * NotifyVRVsync immediately, as it will run unbounded.
   * If NotifyVRVsync is not called here due to SubmitFrame failing, the
   * fallback "watchdog" code in VRDisplayHost::NotifyVSync() will cause
   * frames to continue at a lower refresh rate until frame submission
   * succeeds again.
   */
  VRManager *vm = VRManager::Get();
  MOZ_ASSERT(vm);
  vm->NotifyVRVsync(mDisplayInfo.mDisplayID);
}