Vulkan: unix line endings in generated shaders

Bug: angleproject:3007
Change-Id: I466caa92ae337508ae284b6fb8d38f5fa3ea1042
Reviewed-on: https://chromium-review.googlesource.com/c/1366796
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>

Author: ShabbyX

src/libANGLE/renderer/vulkan/gen_vk_internal_shaders.py

@@ -328,7 +328,7 @@ def compile_variation(shader_file, shader_basename, flags, enums,
         if result != 0:
             raise Exception("Error compiling " + shader_file)
 
-        with open(output_path, 'a') as incfile:
+        with open(output_path, 'ab') as incfile:
             shader_text = subprocess.check_output(glslang_preprocessor_output_args)
 
             incfile.write('\n\n#if 0  // Generated from:\n')