[Impeller] pass const ref to binding helpers.

[jonahwilliams]

No point in passing by value and moving, just pass a const ref through. Trivial performance improvement.

Before

  /// Bind uniform buffer for resource named FragInfo.
  static bool BindFragInfo(ResourceBinder& command, BufferView view) {
    return command.BindResource(ShaderStage::kFragment, kResourceFragInfo, kMetadataFragInfo, std::move(view));
  }

  /// Bind combined image sampler for resource named texture_sampler.
  static bool BindTextureSampler(ResourceBinder& command, std::shared_ptr<const Texture> texture, std::shared_ptr<const Sampler> sampler) {
    return command.BindResource(ShaderStage::kFragment, kResourceTextureSampler, kMetadataTextureSampler, std::move(texture), std::move(sampler));
  }

After

  /// Bind uniform buffer for resource named FragInfo.
  static bool BindFragInfo(ResourceBinder& command, const BufferView& view) {
    return command.BindResource(ShaderStage::kFragment, kResourceFragInfo, kMetadataFragInfo, view);
  }

  /// Bind combined image sampler for resource named texture_sampler.
  static bool BindTextureSampler(ResourceBinder& command, const std::shared_ptr<const Texture>& texture, const std::shared_ptr<const Sampler>& sampler) {
    return command.BindResource(ShaderStage::kFragment, kResourceTextureSampler, kMetadataTextureSampler, texture, sampler);
  }

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[gaaclarke]

It's not guaranteed that this will execute faster. The move may be faster than the reference. It's the cost of the move versus the indirection of accessing by reference.

[jonahwilliams]

But we're not moving into this function, nor is BindResource moving - it takes a reference.

[gaaclarke]

Oh, bind is just taking a reference? The we move just to take a reference anyways? Okay.

[jonahwilliams]

Yeah, i think originally it all moved - then the clang tidy lints told us to make Bind take a reference, but it left this since it is generated code.

[Hixie]

test-exempt: code gen change

[jonahwilliams]

Revert added as there are lint failures in compute tessellator.