Revert of Move DstCopy on gpu into the GrXferProcessor.

gyp/gpu.gypi

 # 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
 #
 {
   'variables': {
     'skgpu_sources': [
@@ skipping 157 matching lines @@
       '<(skia_src_path)/gpu/GrTemplates.h',
       '<(skia_src_path)/gpu/GrTextContext.cpp',
       '<(skia_src_path)/gpu/GrTextContext.h',
       '<(skia_src_path)/gpu/GrFontCache.cpp',
       '<(skia_src_path)/gpu/GrFontCache.h',
       '<(skia_src_path)/gpu/GrTexture.cpp',
       '<(skia_src_path)/gpu/GrTexturePriv.h',
       '<(skia_src_path)/gpu/GrTextureAccess.cpp',
       '<(skia_src_path)/gpu/GrTRecorder.h',
       '<(skia_src_path)/gpu/GrVertexBuffer.h',
-      '<(skia_src_path)/gpu/GrXferProcessor.cpp',
 
       '<(skia_src_path)/gpu/effects/Gr1DKernelEffect.h',
       '<(skia_src_path)/gpu/effects/GrConfigConversionEffect.cpp',
       '<(skia_src_path)/gpu/effects/GrConfigConversionEffect.h',
       '<(skia_src_path)/gpu/effects/GrCoverageSetOpXP.cpp',
       '<(skia_src_path)/gpu/effects/GrCoverageSetOpXP.h',
       '<(skia_src_path)/gpu/effects/GrCustomXfermode.cpp',
       '<(skia_src_path)/gpu/effects/GrCustomXfermodePriv.h',
       '<(skia_src_path)/gpu/effects/GrBezierEffect.cpp',
       '<(skia_src_path)/gpu/effects/GrBezierEffect.h',
@@ skipping 79 matching lines @@
       '<(skia_src_path)/gpu/gl/GrGLTexture.cpp',
       '<(skia_src_path)/gpu/gl/GrGLTexture.h',
       '<(skia_src_path)/gpu/gl/GrGLTextureRenderTarget.h',
       '<(skia_src_path)/gpu/gl/GrGLUtil.cpp',
       '<(skia_src_path)/gpu/gl/GrGLUtil.h',
       '<(skia_src_path)/gpu/gl/GrGLUniformHandle.h',
       '<(skia_src_path)/gpu/gl/GrGLVertexArray.cpp',
       '<(skia_src_path)/gpu/gl/GrGLVertexArray.h',
       '<(skia_src_path)/gpu/gl/GrGLVertexBuffer.cpp',
       '<(skia_src_path)/gpu/gl/GrGLVertexBuffer.h',
-      '<(skia_src_path)/gpu/gl/GrGLXferProcessor.cpp',
-      '<(skia_src_path)/gpu/gl/GrGLXferProcessor.h',
 
       # Files for building GLSL shaders
       '<(skia_src_path)/gpu/gl/builders/GrGLProgramBuilder.cpp',
       '<(skia_src_path)/gpu/gl/builders/GrGLProgramBuilder.h',
       '<(skia_src_path)/gpu/gl/builders/GrGLShaderBuilder.cpp',
       '<(skia_src_path)/gpu/gl/builders/GrGLShaderBuilder.h',
       '<(skia_src_path)/gpu/gl/builders/GrGLShaderStringBuilder.cpp',
       '<(skia_src_path)/gpu/gl/builders/GrGLShaderStringBuilder.h',
       '<(skia_src_path)/gpu/gl/builders/GrGLSLPrettyPrint.cpp',
       '<(skia_src_path)/gpu/gl/builders/GrGLVertexShaderBuilder.cpp',
@@ skipping 81 matching lines @@
     ],
     'skgpu_null_gl_sources': [
       '<(skia_src_path)/gpu/gl/GrGLCreateNullInterface.cpp',
 
       # Sk files
       '<(skia_src_path)/gpu/gl/SkNullGLContext.cpp',
       '<(skia_src_path)/gpu/gl/SkNullGLContext.h',
     ],
   },
 }