Enable extension support and debug layer.

gyp/gpu.gypi

 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 # Include this gypi to include all 'gpu' files
 # The parent gyp/gypi file must define
 #       'skia_src_path'     e.g. skia/trunk/src
 #       'skia_include_path' e.g. skia/trunk/include
 #
 # The skia build defines these in common_variables.gypi
@@ skipping 426 matching lines @@
     'skgpu_vk_sources': [
       '<(skia_include_path)/gpu/vk/GrVkInterface.h',
       '<(skia_src_path)/gpu/vk/GrVkBuffer.cpp',
       '<(skia_src_path)/gpu/vk/GrVkBuffer.h',
       '<(skia_src_path)/gpu/vk/GrVkCaps.cpp',
       '<(skia_src_path)/gpu/vk/GrVkCaps.h',
       '<(skia_src_path)/gpu/vk/GrVkCommandBuffer.cpp',
       '<(skia_src_path)/gpu/vk/GrVkCommandBuffer.h',
       '<(skia_src_path)/gpu/vk/GrVkDescriptorPool.cpp',
       '<(skia_src_path)/gpu/vk/GrVkDescriptorPool.h',
+      '<(skia_src_path)/gpu/vk/GrVkExtensions.cpp',
+      '<(skia_src_path)/gpu/vk/GrVkExtensions.h',
       '<(skia_src_path)/gpu/vk/GrVkFramebuffer.cpp',
       '<(skia_src_path)/gpu/vk/GrVkFramebuffer.h',
       '<(skia_src_path)/gpu/vk/GrVkGpu.cpp',
       '<(skia_src_path)/gpu/vk/GrVkGpu.h',
       '<(skia_src_path)/gpu/vk/GrVkImage.cpp',
       '<(skia_src_path)/gpu/vk/GrVkImage.h',
       '<(skia_src_path)/gpu/vk/GrVkImageView.cpp',
       '<(skia_src_path)/gpu/vk/GrVkImageView.h',
       '<(skia_src_path)/gpu/vk/GrVkIndexBuffer.cpp',
       '<(skia_src_path)/gpu/vk/GrVkIndexBuffer.h',
@@ skipping 98 matching lines @@
       '<(skia_src_path)/gpu/gl/debug/SkDebugGLContext.cpp',
       '<(skia_src_path)/gpu/gl/debug/SkDebugGLContext.h',
     ],
     'skgpu_null_gl_sources': [
       '<(skia_src_path)/gpu/gl/GrGLCreateNullInterface.cpp',
       '<(skia_src_path)/gpu/gl/SkNullGLContext.cpp',
       '<(skia_include_path)/gpu/gl/SkNullGLContext.h',
     ],
   },
 }