Vulkan: Bug fix in sRGBDecode logic When a sampler's GL_TEXTURE_SRGB_DECODE_EXT state was toggled between GL_DECODE_EXT and GL_SKIP_DECODE_EXT VkImageViews of the TextureVk object were not being updated. Add sRGB_decode state as part of ImageViewSubresourceSerial so we retrieve the correct VkImageView from the texture cache. Bug: angleproject:3609 Tests: angle_end2end_tests --gtest_filter=SRGBTextureTestES3.SRGBDecodeSamplerParameterToggle*Vulkan Change-Id: I897e461957d408b5a5b4f03fefc05f2e9684c7b7 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2514900 Commit-Queue: Mohan Maiya <m.maiya@samsung.com> Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>