* changes: support sandboxed rust rules conditionally escape rule builder command Revert^2 "allow Ninja variables in RuleBuilder API" Revert^2 "add crate_root property to rust modules" Revert^2 "add rust_toolchain_rustc_prebuilt module type"
* changes: support sandboxed rust rules conditionally escape rule builder command Revert^2 "allow Ninja variables in RuleBuilder API" Revert^2 "add crate_root property to rust modules" Revert^2 "add rust_toolchain_rustc_prebuilt module type"