Includes fix #3253, which fixed the following SwANGLE test:
KHR-GLES31.core.compute_shader.resources-max

Changes:
    fd773eb50 Start SPIRV-Tools v2020.3
    fd8e13051 Finalize SPIRV-Tools v2020.2
    3ef8fe9a5 Update CHANGES
    022da4d0e Fix identification of Vulkan images and buffers (#3253)
    1346dd5de Disallow phis of images, samplers and sampled images (#3246)
    1c8bda372 Add data structure for DebugScope, DebugDeclare in spirv-opt (#3183)
    e6f372c5c Whitelist SPV_KHR_ray_tracing (#3241)
    7f341ffee Make file formatting comply with POSIX standards (#3242)
    60104cd97 Add opt::Operand::AsCString and AsString (#3240)
    da52d0875 Add RayQueryProvisionalKHR to opt types (#3239)
    18d3896a1 Whitelist SPV_EXT_demote_to_helper_invocation for opt passes (#3236)
    5a97e3a39 Add support for KHR_ray_{query,tracing} extensions (#3235)
    25ede1ced Roll external/spirv-headers/ 30ef660ce..a17e17e36 (1 commit) (#3230)
    7a8f79762 Update dependencies (#3228)
    1fe9bcc10 Instrument: Debug Printf support (#3215)
    6428ad05e spirv-fuzz: Support OpPhi when adding dead break and continue (#3225)
    1af1df3b2 spirv-fuzz: Fix vector width issue in 'add equation instructions' pass (#3223)
    dd3d91691 Allow sampledimage types as operand of OpCopyObject (#3222)
    7c3de218f spirv-fuzz: Remove duplicated functionality (#3220)
    659470446 spirv-fuzz: Allow OpPhi operand to be replaced with a composite synonym (#3221)
    4c027048d spirv-fuzz: Add toggle access chain instruction transformation (#3211)
    533af4981 spirv-fuzz: Add fuzzer pass to permute function parameters (#3212)
    da4cd2148 spirv-fuzz: Use better function name (#3207)
    66a682b6a spirv-fuzz: Add swap commutable operands transformation (#3205)
    044ecc0b2 spirv-fuzz: Fuzzer pass to add equation instructions (#3202)
    a6d3a2dd4 Refactor FuzzerPass::ApplyTransformation code duplication. (#3206)
    e1688b60c Avoid use of Python distutils.dir_util (#3203)
    661e79eec Adding WebGPU specific Workgroup scope rule (#3204)
    70f888131 Add validation rules for OpenCL.DebugInfo.100 extension (#3133)
    fb6e3e48d Combine extinst-name and extinst-output-base into one arg. (#3200)

Commands:
    ./third_party/update-spirvtools.sh

Bug: b/123642959
Bug: b/148460089
Change-Id: I8fa5d3609de1c6ae786c84b93cba7ac015b4f56e