Move GrDrawAtlasBatch to separate file

Committed: https://skia.googlesource.com/skia/+/b091c44c33edbad3466601b29d60bc2eaa4453fa

Review URL: https://codereview.chromium.org/1274013003
diff --git a/gyp/gpu.gypi b/gyp/gpu.gypi
index f3f0157..ecb32cb 100644
--- a/gyp/gpu.gypi
+++ b/gyp/gpu.gypi
@@ -223,6 +223,8 @@
       # Batches
       '<(skia_src_path)/gpu/batches/GrBatch.cpp',
       '<(skia_src_path)/gpu/batches/GrBatch.h',
+      '<(skia_src_path)/gpu/batches/GrDrawAtlasBatch.cpp',
+      '<(skia_src_path)/gpu/batches/GrDrawAtlasBatch.h',
       '<(skia_src_path)/gpu/batches/GrRectBatch.h',
       '<(skia_src_path)/gpu/batches/GrRectBatch.cpp',
       '<(skia_src_path)/gpu/batches/GrStrokeRectBatch.cpp',