[Tizen] Re-implemented render external texture gl for impeller to avoid change FlutterOpenGLTexture and use deprecated api

[xiaowei-guan]

We have supported render external texture gl for Impeller flutter-tizen/engine#368
But this PR has two issues:

1. It modify FlutterOpenGLTexture, it added additional variables, not a good design.

  /// The pixel data buffer.
  const uint8_t* buffer;
  /// The size of pixel buffer.
  size_t buffer_size;
  /// Callback invoked that the gpu surface texture start binding.
  BoolCallback bind_callback;
  /// The type of the texture.
  FlutterGLImpellerTextureType impeller_texture_type;

2. It uses Deprecated API

  // Deprecated: use BlitPass::AddCopy instead.
  [[nodiscard]] bool SetContents(const uint8_t* contents,
                                 size_t length,
                                 size_t slice = 0,
                                 bool is_opaque = false);

So I tried to revert offical PR to render external gl for impeller flutter/engine#56277
But this PR doesn't work on Tizen platform, I think This PR may not have been verified.
To avoid change FlutterOpenGLTexture and use deprecated api, so I re-implemented render external texture gl for impeller based on this offical PR.
Fix flutter-tizen/embedder#131

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