Cannot build Servo on MacOS because of an error in mozangle's build.rs.

[bgergely0]

The #include <array> line in gfx/angle/checkout/include/GLSLANG/ShaderLang.h is not working on MacOS.

This is breaking ./mach build on a fresh servo clone (servo commit: 6bad65a5a16c5a90b09fe8d0441c1d473e46e060)

--- stderr
  gfx/angle/checkout/include/GLSLANG/ShaderLang.h:13:10: fatal error: 'array' file not found

  thread 'main' panicked at [...]/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/mozangle-0.5.3/build.rs:371:10:
  Should generate shader bindings: ClangDiagnostic("gfx/angle/checkout/include/GLSLANG/ShaderLang.h:13:10: fatal error: 'array' file not found\n")

[sagudev]

IIRC this happens if you have multiple clangs installed.