Fix up gles2 thunk targets a bit

mojo/public/gles2/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.
 
 # In an is_component_build build, everything can link against //mojo/gles2
 # because it is built as a shared library. However, in a static build,
 # //mojo/gles2 is linked into an executable (e.g., mojo_shell), and must be
 # injected into other shared libraries (i.e., Mojo Apps) that need the mojo
 # gles2 API.
 #
 # For component targets, add //mojo/public/gles2:for_component to your deps
 # section.
 #
 # For shared_library targets (e.g., a Mojo App), add
 # //mojo/public/gles2:for_shared_library to your deps
 
 group("for_shared_library") {
+  public_configs = [ "//third_party/khronos:khronos_headers" ]
+  public_deps = [ "//mojo/public/c/gles2" ]
+
   if (is_component_build) {
     deps = [ "//mojo/gles2" ]
   } else {
-    deps = [ ":gles2" ]
+    deps = [ "//mojo/public/platform/native:gles2_thunks" ]
   }
 }
 
 group("for_component") {
+  public_configs = [ "//third_party/khronos:khronos_headers" ]
+  public_deps = [ "//mojo/public/c/gles2" ]
+
   if (is_component_build) {
     deps = [ "//mojo/gles2" ]
   }
 }
-
-# GYP version: mojo/mojo_public.gypi:mojo_gles2
-static_library("gles2") {
-  visibility = [ ":for_shared_library" ]
-
-  sources = [
-    "../platform/native/gles2_thunks.cc",
-    "../platform/native/gles2_thunks.h",
-    "../platform/native/gles2_impl_thunks.cc",
-    "../platform/native/gles2_impl_thunks.h",
-    "../platform/native/gles2_impl_chromium_texture_mailbox_thunks.cc",
-    "../platform/native/gles2_impl_chromium_texture_mailbox_thunks.h",
-    "../platform/native/gles2_impl_chromium_sync_point_thunks.cc",
-    "../platform/native/gles2_impl_chromium_sync_point_thunks.h",
-    "gles2_interface.h",
-  ]
-
-  public_configs = [ "//third_party/khronos:khronos_headers" ]
-
-  public_deps = [ "//mojo/public/c/gles2" ]
-
-  defines = [
-    "MOJO_GLES2_IMPLEMENTATION",
-  ]
-  deps = [
-    "//mojo/public/c/environment",
-    "//mojo/public/c/system",
-  ]
-
-  if (is_mac) {
-    # TODO(GYP): Make it a run-path dependent library.
-    # 'DYLIB_INSTALL_NAME_BASE': '@loader_path',
-  }
-}