Add a base class for GrIODB that handles geometry data

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 60 matching lines @@
       '<(skia_src_path)/gpu/GrDefaultGeoProcFactory.h',
       '<(skia_src_path)/gpu/GrDefaultPathRenderer.cpp',
       '<(skia_src_path)/gpu/GrDefaultPathRenderer.h',
       '<(skia_src_path)/gpu/GrDistanceFieldTextContext.h',
       '<(skia_src_path)/gpu/GrDistanceFieldTextContext.cpp',
       '<(skia_src_path)/gpu/GrDrawState.cpp',
       '<(skia_src_path)/gpu/GrDrawState.h',
       '<(skia_src_path)/gpu/GrDrawTarget.cpp',
       '<(skia_src_path)/gpu/GrDrawTarget.h',
       '<(skia_src_path)/gpu/GrDrawTargetCaps.h',
+      '<(skia_src_path)/gpu/GrFlushToGpuDrawTarget.cpp',
+      '<(skia_src_path)/gpu/GrFlushToGpuDrawTarget.h',
       '<(skia_src_path)/gpu/GrFontScaler.cpp',
       '<(skia_src_path)/gpu/GrFontScaler.h',
       '<(skia_src_path)/gpu/GrGeometryBuffer.h',
       '<(skia_src_path)/gpu/GrGeometryData.h',
       '<(skia_src_path)/gpu/GrGeometryProcessor.h',
       '<(skia_src_path)/gpu/GrGlyph.h',
       '<(skia_src_path)/gpu/GrGpu.cpp',
       '<(skia_src_path)/gpu/GrGpu.h',
       '<(skia_src_path)/gpu/GrGpuResourceCacheAccess.h',
       '<(skia_src_path)/gpu/GrGpuResource.cpp',
@@ skipping 266 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',
     ],
   },
 }