Add shaderc to DEPS to roll in script

Also adds in forwarding commandline args.

BUG=chromium:979206

Change-Id: I29f7de40d88e71edae6b9f324ce502193263afbb
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/8400
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>

scripts/roll-shaderc-deps.sh

diff --git a/scripts/roll-shaderc-deps.sh b/scripts/roll-shaderc-deps.sh
index 9958d38..b2d78ff4 100755
--- a/scripts/roll-shaderc-deps.sh
+++ b/scripts/roll-shaderc-deps.sh
@@ -23,10 +23,11 @@
 repo_path=$(dirname "$0")/..
 
 glslang_dir="third_party/glslang/"
+shaderc_dir="third_party/shaderc/"
 spirv_cross_dir="third_party/spirv-cross/"
 spirv_headers_dir="third_party/spirv-headers/"
 spirv_tools_dir="third_party/SPIRV-Tools/"
 
 cd "$repo_path"
 
-roll-dep "${glslang_dir}" "${spirv_cross_dir}" "${spirv_headers_dir}" "${spirv_tools_dir}"
+roll-dep "$@" "${glslang_dir}" "${shaderc_dir}" "${spirv_cross_dir}" "${spirv_headers_dir}" "${spirv_tools_dir}"