upb: clean up upb/json/BUILD

- Match build target names to their corresponding file names (remove stuttering)
- Replace a dep on (deprecated) :upb with a dep on :wire
- Mark :struct_upb_proto as testonly
- Group the cc_test targets together

PiperOrigin-RevId: 541408625

upb/json/BUILD

@@ -1,9 +1,6 @@
 # TODO(haberman): describe this package.
 
-load(
-    "//bazel:build_defs.bzl",
-    "UPB_DEFAULT_COPTS",
-)
+load("//bazel:build_defs.bzl", "UPB_DEFAULT_COPTS")
 load(
     "//bazel:upb_proto_library.bzl",
     "upb_proto_library",
@@ -27,7 +24,21 @@ cc_library(
         "//:lex",
         "//:port",
         "//:reflection",
+        "//:wire",
+    ],
+)
+
+cc_test(
+    name = "decode_test",
+    srcs = ["decode_test.cc"],
+    deps = [
+        ":json",
+        ":struct_upb_proto",
+        ":test_upb_proto",
+        ":test_upb_proto_reflection",
+        "//:reflection",
         "//:upb",
+        "@com_google_googletest//:gtest_main",
     ],
 )
 
@@ -36,9 +47,9 @@ cc_test(
     srcs = ["encode_test.cc"],
     deps = [
         ":json",
-        ":json_test_upb_proto",
-        ":json_test_upb_proto_reflection",
         ":struct_upb_proto",
+        ":test_upb_proto",
+        ":test_upb_proto_reflection",
         "//:reflection",
         "//:upb",
         "@com_google_googletest//:gtest_main",
@@ -46,39 +57,27 @@ cc_test(
 )
 
 proto_library(
-    name = "json_test_proto",
+    name = "test_proto",
     testonly = 1,
     srcs = ["test.proto"],
     deps = ["@com_google_protobuf//:struct_proto"],
 )
 
 upb_proto_library(
-    name = "json_test_upb_proto",
+    name = "test_upb_proto",
     testonly = 1,
-    deps = [":json_test_proto"],
+    deps = [":test_proto"],
 )
 
 upb_proto_reflection_library(
-    name = "json_test_upb_proto_reflection",
+    name = "test_upb_proto_reflection",
     testonly = 1,
-    deps = [":json_test_proto"],
-)
-
-cc_test(
-    name = "json_decode_test",
-    srcs = ["decode_test.cc"],
-    deps = [
-        ":json",
-        ":json_test_upb_proto",
-        ":json_test_upb_proto_reflection",
-        ":struct_upb_proto",
-        "//:reflection",
-        "//:upb",
-        "@com_google_googletest//:gtest_main",
-    ],
+    deps = [":test_proto"],
 )
 
+# TODO: This target arguably belongs in //google/protobuf/BUILD
 upb_proto_library(
     name = "struct_upb_proto",
+    testonly = 1,
     deps = ["@com_google_protobuf//:struct_proto"],
 )