Include third_party_deps cmake files.

PiperOrigin-RevId: 828957097
Change-Id: I2aeea2ae9e2621c8c62a34095af6ea8fd0797f08

cmake/third_party_deps/sdl2.cmake

@@ -0,0 +1,28 @@
+# Copyright 2025 DeepMind Technologies Limited
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set(MUJOCO_DEP_VERSION_sdl2
+    98d1f3a45aae568ccd6ed5fec179330f47d4d356
+    CACHE STRING "Version of `SDL2` to be fetched."
+)
+mark_as_advanced(MUJOCO_DEP_VERSION_sdl2)
+
+include(FindOrFetch)
+
+set(SDL_SHARED_ENABLED_BY_DEFAULT OFF)
+fetchpackage(
+    PACKAGE_NAME  sdl2
+    GIT_REPO      https://github.com/libsdl-org/SDL.git
+    GIT_TAG       ${MUJOCO_DEP_VERSION_sdl2}
+)