gpu: Make glTexSubImage2D work with GL_SRGB_ALPHA on OpenGL

gpu/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # GYP-to-GN project mappings:
 #
 #  gpu.gyp:command_buffer_client => //gpu/command_buffer/client
 #
 #  gpu.gyp:command_buffer_common => //gpu/command_buffer/common
 #
@@ skipping 109 matching lines @@
     "command_buffer/tests/compressed_texture_test.cc",
     "command_buffer/tests/es3_misc_functions_unittest.cc",
     "command_buffer/tests/gl_bind_uniform_location_unittest.cc",
     "command_buffer/tests/gl_chromium_framebuffer_multisample_unittest.cc",
     "command_buffer/tests/gl_chromium_path_rendering_unittest.cc",
     "command_buffer/tests/gl_clear_framebuffer_unittest.cc",
     "command_buffer/tests/gl_compressed_copy_texture_CHROMIUM_unittest.cc",
     "command_buffer/tests/gl_copy_texture_CHROMIUM_unittest.cc",
     "command_buffer/tests/gl_cube_map_texture_unittest.cc",
     "command_buffer/tests/gl_depth_texture_unittest.cc",
+    "command_buffer/tests/gl_ext_srgb_unittest.cc",
     "command_buffer/tests/gl_fence_sync_unittest.cc",
     "command_buffer/tests/gl_gpu_memory_buffer_unittest.cc",
     "command_buffer/tests/gl_lose_context_chromium_unittest.cc",
     "command_buffer/tests/gl_manager.cc",
     "command_buffer/tests/gl_manager.h",
     "command_buffer/tests/gl_pointcoord_unittest.cc",
     "command_buffer/tests/gl_program_unittest.cc",
     "command_buffer/tests/gl_query_unittest.cc",
     "command_buffer/tests/gl_readback_unittest.cc",
     "command_buffer/tests/gl_shared_resources_unittest.cc",
@@ skipping 204 matching lines @@
 if (is_win || is_linux || is_mac) {
   # TODO(GYP): Delete this after we've converted everything to GN.
   # The _run targets exist only for compatibility w/ GYP.
   group("angle_end2end_tests_run") {
     testonly = true
     deps = [
       "//third_party/angle/src/tests:angle_end2end_tests",
     ]
   }
 }