Condense namespaces in tint/fuzzers.

This PR condenses the namespaces in the tint/fuzzers folder.

Change-Id: I74d4db39e41d408a826bee89241c5752e1aa7df9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/86036
Reviewed-by: Ben Clayton <bclayton@google.com>
Auto-Submit: Dan Sinclair <dsinclair@chromium.org>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>
diff --git a/src/tint/fuzzers/tint_spv_reader_spv_writer_fuzzer.cc b/src/tint/fuzzers/tint_spv_reader_spv_writer_fuzzer.cc
index b3cc6b0..c95034a 100644
--- a/src/tint/fuzzers/tint_spv_reader_spv_writer_fuzzer.cc
+++ b/src/tint/fuzzers/tint_spv_reader_spv_writer_fuzzer.cc
@@ -17,8 +17,7 @@
 #include "src/tint/fuzzers/fuzzer_init.h"
 #include "src/tint/fuzzers/tint_reader_writer_fuzzer.h"
 
-namespace tint {
-namespace fuzzers {
+namespace tint::fuzzers {
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
   DataBuilder db(data, size);
@@ -33,5 +32,4 @@
   return fuzzer.Run(data, size);
 }
 
-}  // namespace fuzzers
-}  // namespace tint
+}  // namespace tint::fuzzers