Add glslang.js via cipd.

This will be used by the WebGPU CTS to compile GLSL shaders at runtime:
https://chromium-review.googlesource.com/c/chromium/src/+/2100018

The compiler is around 1MB, and is rebuilt with some frequency, so we
avoid checking it into WPT or Chromium. And since WebGPU has decided not
to use SPIR-V, this solution is temporary until we have an
implementation and testing of WGSL shaders.

glslang.js is a WASM build of glslang, which currently also exists in
src/third_party/glslang.

Bug: 1060911
Change-Id: I7665b9d7137549466ac9409852e4dd32cc678663
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2100016
Commit-Queue: Kai Ninomiya <kainino@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#755039}

DEPS

@@ -1447,6 +1447,16 @@ deps = {
   'src/third_party/webgpu-cts/src':
     Var('chromium_git') + '/external/github.com/gpuweb/cts.git' + '@' + '84ee597cdeae08bb26e578fc66a35bcf35f633f4',
 
+  'src/third_party/blink/web_tests/wpt_internal/webgpu/third_party/glslang_js': {
+    'packages': [
+      {
+        'package': 'chromium/third_party/glslang_js',
+        'version': 'IB6pL73YKdgoiK7Ea7U5Uw_XjzXGZJCB0I3LhaiYY-sC',
+      },
+    ],
+    'dep_type': 'cipd',
+  },
+
   'src/third_party/webrtc':
     Var('webrtc_git') + '/src.git' + '@' + '4b425aeef9cded872488aea32aa5d711be43b935',
 

third_party/blink/web_tests/wpt_internal/webgpu/third_party/glslang_js/LICENSE

+Copyright (c) 2015-2016 The Khronos Group Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and/or associated documentation files (the
+"Materials"), to deal in the Materials without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Materials, and to
+permit persons to whom the Materials are furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Materials.
+
+MODIFICATIONS TO THIS FILE MAY MEAN IT NO LONGER ACCURATELY REFLECTS
+KHRONOS STANDARDS. THE UNMODIFIED, NORMATIVE VERSIONS OF KHRONOS
+SPECIFICATIONS AND HEADER INFORMATION ARE LOCATED AT
+   https://www.khronos.org/registry/
+
+THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.

third_party/blink/web_tests/wpt_internal/webgpu/third_party/glslang_js/OWNERS

+# This directory already inherits owner '*', so these owners are informational.
+kainino@chromium.org
+cwallez@chromium.org
+enga@chromium.org

third_party/blink/web_tests/wpt_internal/webgpu/third_party/glslang_js/README.chromium

+Name: JS+WASM build of glslang (Khronos reference front-end for GLSL and ESSL)
+Short Name: glslang.js
+URL: https://github.com/kainino0x/-webgpu-glslang
+Version: 0.0.15
+Revision: 6f3bd3ec25393a41a090b4644935336b5430cb23
+Security Critical: no
+License: MIT
+License File: LICENSE
+
+Description:
+JS+WASM build of glslang.
+
+glslang is an OpenGL and OpenGL ES shader front end and validator.
+
+See https://github.com/kainino0x/glslang.js for info on rebuilding.
+The latest binary was built with `build.sh` on macOS with Emscripten 1.39.7
+and uploaded to CIPD with `cipd create --pkg-def cipd.yaml`.

third_party/blink/web_tests/wpt_internal/webgpu/third_party/glslang_js/cipd.yaml

+package: chromium/third_party/glslang_js
+description: 'JS+WASM build of glslang (Khronos reference front-end for GLSL and ESSL)'
+data:
+  - file: lib/glslang.js
+  - file: lib/glslang.wasm

third_party/blink/web_tests/wpt_internal/webgpu/third_party/glslang_js/lib/.gitignore

+/glslang.js
+/glslang.wasm