[shuffle] Move sem to new structure.

This CL moves the sem folder into the `lang/wgsl/sem` folder and
updates the includes. The namespaces and build groups are not updated in
this CL, just the code move.

Bug: tint:1988
Change-Id: I910072b7384ab7622e502034b13bf0f421024ef6
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/142040
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
diff --git a/src/tint/resolver/load_test.cc b/src/tint/resolver/load_test.cc
index 48b9886..d7ca8ab 100644
--- a/src/tint/resolver/load_test.cc
+++ b/src/tint/resolver/load_test.cc
@@ -12,11 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "src/tint/sem/load.h"
+#include "src/tint/lang/wgsl/sem/load.h"
 #include "gmock/gmock.h"
+#include "src/tint/lang/wgsl/sem/test_helper.h"
 #include "src/tint/resolver/resolver.h"
 #include "src/tint/resolver/resolver_test_helper.h"
-#include "src/tint/sem/test_helper.h"
 #include "src/tint/type/reference.h"
 #include "src/tint/type/texture_dimension.h"