Remove some test files not used.
diff --git a/objectivec/DevTools/compile_testing_protos.sh b/objectivec/DevTools/compile_testing_protos.sh
index 604a5b5..8bc6643 100755
--- a/objectivec/DevTools/compile_testing_protos.sh
+++ b/objectivec/DevTools/compile_testing_protos.sh
@@ -32,24 +32,13 @@
 
 CORE_PROTO_FILES=(
   src/google/protobuf/any_test.proto
-  src/google/protobuf/unittest_arena.proto
-  src/google/protobuf/unittest_custom_options.proto
-  src/google/protobuf/unittest_enormous_descriptor.proto
-  src/google/protobuf/unittest_embed_optimize_for.proto
-  src/google/protobuf/unittest_empty.proto
   src/google/protobuf/unittest_import.proto
-  src/google/protobuf/unittest_import_lite.proto
-  src/google/protobuf/unittest_lite.proto
   src/google/protobuf/unittest_mset.proto
   src/google/protobuf/unittest_mset_wire_format.proto
-  src/google/protobuf/unittest_no_generic_services.proto
-  src/google/protobuf/unittest_optimize_for.proto
   src/google/protobuf/unittest.proto
   src/google/protobuf/unittest_import_public.proto
   src/google/protobuf/unittest_import_public_lite.proto
-  src/google/protobuf/unittest_drop_unknown_fields.proto
   src/google/protobuf/unittest_preserve_unknown_enum.proto
-  src/google/protobuf/map_lite_unittest.proto
   src/google/protobuf/map_proto2_unittest.proto
   src/google/protobuf/map_unittest.proto
   # The unittest_custom_options.proto extends the messages in descriptor.proto
diff --git a/objectivec/ProtocolBuffers_OSX.xcodeproj/project.pbxproj b/objectivec/ProtocolBuffers_OSX.xcodeproj/project.pbxproj
index 365fdc3..839c158 100644
--- a/objectivec/ProtocolBuffers_OSX.xcodeproj/project.pbxproj
+++ b/objectivec/ProtocolBuffers_OSX.xcodeproj/project.pbxproj
@@ -62,7 +62,6 @@
 		F40EE4C0206BF8B90071091A /* GPBCompileTest22.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE48A206BF8B00071091A /* GPBCompileTest22.m */; };
 		F40EE4C1206BF8B90071091A /* GPBCompileTest23.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE487206BF8B00071091A /* GPBCompileTest23.m */; };
 		F40EE50B206C06640071091A /* GPBCompileTest24.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE508206C06440071091A /* GPBCompileTest24.m */; };
-		F40EE50C206C06640071091A /* GPBCompileTest25.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE507206C06440071091A /* GPBCompileTest25.m */; };
 		F41C175D1833D3310064ED4D /* GPBPerfTests.m in Sources */ = {isa = PBXBuildFile; fileRef = F41C175C1833D3310064ED4D /* GPBPerfTests.m */; };
 		F4353D1D1AB8822D005A6198 /* GPBDescriptorTests.m in Sources */ = {isa = PBXBuildFile; fileRef = F4353D1C1AB8822D005A6198 /* GPBDescriptorTests.m */; };
 		F4353D231ABB1537005A6198 /* GPBDictionary.m in Sources */ = {isa = PBXBuildFile; fileRef = F4353D211ABB1537005A6198 /* GPBDictionary.m */; };
@@ -205,7 +204,6 @@
 		F40EE491206BF8B10071091A /* GPBCompileTest03.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest03.m; sourceTree = "<group>"; };
 		F40EE492206BF8B10071091A /* GPBCompileTest06.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest06.m; sourceTree = "<group>"; };
 		F40EE493206BF8B20071091A /* GPBCompileTest11.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest11.m; sourceTree = "<group>"; };
-		F40EE507206C06440071091A /* GPBCompileTest25.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest25.m; sourceTree = "<group>"; };
 		F40EE508206C06440071091A /* GPBCompileTest24.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest24.m; sourceTree = "<group>"; };
 		F41C175C1833D3310064ED4D /* GPBPerfTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBPerfTests.m; sourceTree = "<group>"; };
 		F4353D1C1AB8822D005A6198 /* GPBDescriptorTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBDescriptorTests.m; sourceTree = "<group>"; };
@@ -472,7 +470,6 @@
 				F40EE48A206BF8B00071091A /* GPBCompileTest22.m */,
 				F40EE487206BF8B00071091A /* GPBCompileTest23.m */,
 				F40EE508206C06440071091A /* GPBCompileTest24.m */,
-				F40EE507206C06440071091A /* GPBCompileTest25.m */,
 				5102DABB1891A052002037B6 /* GPBConcurrencyTests.m */,
 				F4353D1C1AB8822D005A6198 /* GPBDescriptorTests.m */,
 				F4C4B9E21E1D974F00D3B61D /* GPBDictionaryTests.m */,
@@ -772,7 +769,6 @@
 				F4F8D8831D789FD9002CE128 /* GPBUnittestProtos2.m in Sources */,
 				F4353D1D1AB8822D005A6198 /* GPBDescriptorTests.m in Sources */,
 				8B4248BB1A8C256A00BC1EC6 /* GPBSwiftTests.swift in Sources */,
-				F40EE50C206C06640071091A /* GPBCompileTest25.m in Sources */,
 				F4584D821ECCB52A00803AB6 /* GPBExtensionRegistryTest.m in Sources */,
 				8BFF9D1A23AD582300E63E32 /* GPBMessageTests+ClassNames.m in Sources */,
 				5102DABC1891A073002037B6 /* GPBConcurrencyTests.m in Sources */,
diff --git a/objectivec/ProtocolBuffers_iOS.xcodeproj/project.pbxproj b/objectivec/ProtocolBuffers_iOS.xcodeproj/project.pbxproj
index 03e0580..e0c24d1 100644
--- a/objectivec/ProtocolBuffers_iOS.xcodeproj/project.pbxproj
+++ b/objectivec/ProtocolBuffers_iOS.xcodeproj/project.pbxproj
@@ -62,7 +62,6 @@
 		F40EE505206BF91E0071091A /* GPBCompileTest22.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE4CF206BF9170071091A /* GPBCompileTest22.m */; };
 		F40EE506206BF91E0071091A /* GPBCompileTest23.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE4CC206BF9170071091A /* GPBCompileTest23.m */; };
 		F40EE511206C068D0071091A /* GPBCompileTest24.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE50E206C06880071091A /* GPBCompileTest24.m */; };
-		F40EE512206C068D0071091A /* GPBCompileTest25.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE50D206C06880071091A /* GPBCompileTest25.m */; };
 		F41C175D1833D3310064ED4D /* GPBPerfTests.m in Sources */ = {isa = PBXBuildFile; fileRef = F41C175C1833D3310064ED4D /* GPBPerfTests.m */; };
 		F4353D1F1AB88243005A6198 /* GPBDescriptorTests.m in Sources */ = {isa = PBXBuildFile; fileRef = F4353D1E1AB88243005A6198 /* GPBDescriptorTests.m */; };
 		F4353D271ABB156F005A6198 /* GPBDictionary.m in Sources */ = {isa = PBXBuildFile; fileRef = F4353D251ABB156F005A6198 /* GPBDictionary.m */; };
@@ -206,7 +205,6 @@
 		F40EE4D6206BF9190071091A /* GPBCompileTest03.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest03.m; sourceTree = "<group>"; };
 		F40EE4D7206BF9190071091A /* GPBCompileTest06.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest06.m; sourceTree = "<group>"; };
 		F40EE4D8206BF9190071091A /* GPBCompileTest11.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest11.m; sourceTree = "<group>"; };
-		F40EE50D206C06880071091A /* GPBCompileTest25.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest25.m; sourceTree = "<group>"; };
 		F40EE50E206C06880071091A /* GPBCompileTest24.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest24.m; sourceTree = "<group>"; };
 		F41C175C1833D3310064ED4D /* GPBPerfTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBPerfTests.m; sourceTree = "<group>"; };
 		F4353D1E1AB88243005A6198 /* GPBDescriptorTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBDescriptorTests.m; sourceTree = "<group>"; };
@@ -478,7 +476,6 @@
 				F40EE4CF206BF9170071091A /* GPBCompileTest22.m */,
 				F40EE4CC206BF9170071091A /* GPBCompileTest23.m */,
 				F40EE50E206C06880071091A /* GPBCompileTest24.m */,
-				F40EE50D206C06880071091A /* GPBCompileTest25.m */,
 				5102DABB1891A052002037B6 /* GPBConcurrencyTests.m */,
 				F4353D1E1AB88243005A6198 /* GPBDescriptorTests.m */,
 				F4C4B9E51E1D97BB00D3B61D /* GPBDictionaryTests.m */,
@@ -779,7 +776,6 @@
 				F4F8D8861D78A193002CE128 /* GPBUnittestProtos2.m in Sources */,
 				F4B51B1C1BBC5C7100744318 /* GPBObjectiveCPlusPlusTest.mm in Sources */,
 				8B4248B41A8BD96E00BC1EC6 /* GPBSwiftTests.swift in Sources */,
-				F40EE512206C068D0071091A /* GPBCompileTest25.m in Sources */,
 				F4584D831ECCB53600803AB6 /* GPBExtensionRegistryTest.m in Sources */,
 				8BFF9D1C23AD593C00E63E32 /* GPBMessageTests+ClassNames.m in Sources */,
 				5102DABC1891A073002037B6 /* GPBConcurrencyTests.m in Sources */,
diff --git a/objectivec/ProtocolBuffers_tvOS.xcodeproj/project.pbxproj b/objectivec/ProtocolBuffers_tvOS.xcodeproj/project.pbxproj
index c7a8d85..73bac63 100644
--- a/objectivec/ProtocolBuffers_tvOS.xcodeproj/project.pbxproj
+++ b/objectivec/ProtocolBuffers_tvOS.xcodeproj/project.pbxproj
@@ -62,7 +62,6 @@
 		F40EE505206BF91E0071091A /* GPBCompileTest22.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE4CF206BF9170071091A /* GPBCompileTest22.m */; };
 		F40EE506206BF91E0071091A /* GPBCompileTest23.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE4CC206BF9170071091A /* GPBCompileTest23.m */; };
 		F40EE511206C068D0071091A /* GPBCompileTest24.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE50E206C06880071091A /* GPBCompileTest24.m */; };
-		F40EE512206C068D0071091A /* GPBCompileTest25.m in Sources */ = {isa = PBXBuildFile; fileRef = F40EE50D206C06880071091A /* GPBCompileTest25.m */; };
 		F41C175D1833D3310064ED4D /* GPBPerfTests.m in Sources */ = {isa = PBXBuildFile; fileRef = F41C175C1833D3310064ED4D /* GPBPerfTests.m */; };
 		F4353D1F1AB88243005A6198 /* GPBDescriptorTests.m in Sources */ = {isa = PBXBuildFile; fileRef = F4353D1E1AB88243005A6198 /* GPBDescriptorTests.m */; };
 		F4353D271ABB156F005A6198 /* GPBDictionary.m in Sources */ = {isa = PBXBuildFile; fileRef = F4353D251ABB156F005A6198 /* GPBDictionary.m */; };
@@ -206,7 +205,6 @@
 		F40EE4D6206BF9190071091A /* GPBCompileTest03.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest03.m; sourceTree = "<group>"; };
 		F40EE4D7206BF9190071091A /* GPBCompileTest06.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest06.m; sourceTree = "<group>"; };
 		F40EE4D8206BF9190071091A /* GPBCompileTest11.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest11.m; sourceTree = "<group>"; };
-		F40EE50D206C06880071091A /* GPBCompileTest25.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest25.m; sourceTree = "<group>"; };
 		F40EE50E206C06880071091A /* GPBCompileTest24.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBCompileTest24.m; sourceTree = "<group>"; };
 		F41C175C1833D3310064ED4D /* GPBPerfTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBPerfTests.m; sourceTree = "<group>"; };
 		F4353D1E1AB88243005A6198 /* GPBDescriptorTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = GPBDescriptorTests.m; sourceTree = "<group>"; };
@@ -478,7 +476,6 @@
 				F40EE4CF206BF9170071091A /* GPBCompileTest22.m */,
 				F40EE4CC206BF9170071091A /* GPBCompileTest23.m */,
 				F40EE50E206C06880071091A /* GPBCompileTest24.m */,
-				F40EE50D206C06880071091A /* GPBCompileTest25.m */,
 				5102DABB1891A052002037B6 /* GPBConcurrencyTests.m */,
 				F4353D1E1AB88243005A6198 /* GPBDescriptorTests.m */,
 				F4C4B9E51E1D97BB00D3B61D /* GPBDictionaryTests.m */,
@@ -779,7 +776,6 @@
 				F4F8D8861D78A193002CE128 /* GPBUnittestProtos2.m in Sources */,
 				F4B51B1C1BBC5C7100744318 /* GPBObjectiveCPlusPlusTest.mm in Sources */,
 				8B4248B41A8BD96E00BC1EC6 /* GPBSwiftTests.swift in Sources */,
-				F40EE512206C068D0071091A /* GPBCompileTest25.m in Sources */,
 				F4584D831ECCB53600803AB6 /* GPBExtensionRegistryTest.m in Sources */,
 				8BFF9D1E23AD599400E63E32 /* GPBMessageTests+ClassNames.m in Sources */,
 				5102DABC1891A073002037B6 /* GPBConcurrencyTests.m in Sources */,
diff --git a/objectivec/Tests/GPBARCUnittestProtos.m b/objectivec/Tests/GPBARCUnittestProtos.m
index 29f6ccf..bd5f261 100644
--- a/objectivec/Tests/GPBARCUnittestProtos.m
+++ b/objectivec/Tests/GPBARCUnittestProtos.m
@@ -40,24 +40,15 @@
 #import "google/protobuf/Descriptor.pbobjc.h"
 
 #import "google/protobuf/Unittest.pbobjc.h"
-#import "google/protobuf/UnittestCustomOptions.pbobjc.h"
 #import "google/protobuf/UnittestCycle.pbobjc.h"
 #import "google/protobuf/UnittestDeprecated.pbobjc.h"
 #import "google/protobuf/UnittestDeprecatedFile.pbobjc.h"
-#import "google/protobuf/UnittestDropUnknownFields.pbobjc.h"
-#import "google/protobuf/UnittestEmbedOptimizeFor.pbobjc.h"
-#import "google/protobuf/UnittestEmpty.pbobjc.h"
-#import "google/protobuf/UnittestEnormousDescriptor.pbobjc.h"
 #import "google/protobuf/UnittestImport.pbobjc.h"
-#import "google/protobuf/UnittestImportLite.pbobjc.h"
 #import "google/protobuf/UnittestImportPublic.pbobjc.h"
 #import "google/protobuf/UnittestImportPublicLite.pbobjc.h"
-#import "google/protobuf/UnittestLite.pbobjc.h"
 #import "google/protobuf/UnittestMset.pbobjc.h"
-#import "google/protobuf/UnittestNoGenericServices.pbobjc.h"
 #import "google/protobuf/UnittestObjc.pbobjc.h"
 #import "google/protobuf/UnittestObjcStartup.pbobjc.h"
-#import "google/protobuf/UnittestOptimizeFor.pbobjc.h"
 #import "google/protobuf/UnittestPreserveUnknownEnum.pbobjc.h"
 #import "google/protobuf/UnittestRuntimeProto2.pbobjc.h"
 #import "google/protobuf/UnittestRuntimeProto3.pbobjc.h"
diff --git a/objectivec/Tests/GPBCompileTest25.m b/objectivec/Tests/GPBCompileTest25.m
deleted file mode 100644
index 7a482b5..0000000
--- a/objectivec/Tests/GPBCompileTest25.m
+++ /dev/null
@@ -1,42 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-
-// This is a test including a single header to ensure things build. This
-// is NOT a public header of the library, but uses a file that defines
-// extensions to proto2 syntax messages, so it can need more things
-// that the proto3 syntax WKTs bundled with the library.
-
-#import "google/protobuf/UnittestCustomOptions.pbobjc.h"
-
-
-// Something in the body of this file so the compiler/linker won't complain
-// about an empty .o file.
-__attribute__((visibility("default"))) char dummy_symbol_25 = 0;
diff --git a/objectivec/Tests/GPBMessageTests+Serialization.m b/objectivec/Tests/GPBMessageTests+Serialization.m
index bb63ec3..3d920e0 100644
--- a/objectivec/Tests/GPBMessageTests+Serialization.m
+++ b/objectivec/Tests/GPBMessageTests+Serialization.m
@@ -37,7 +37,6 @@
 #import "google/protobuf/MapProto2Unittest.pbobjc.h"
 #import "google/protobuf/MapUnittest.pbobjc.h"
 #import "google/protobuf/Unittest.pbobjc.h"
-#import "google/protobuf/UnittestDropUnknownFields.pbobjc.h"
 #import "google/protobuf/UnittestPreserveUnknownEnum.pbobjc.h"
 #import "google/protobuf/UnittestRuntimeProto2.pbobjc.h"
 #import "google/protobuf/UnittestRuntimeProto3.pbobjc.h"
diff --git a/objectivec/Tests/GPBUnittestProtos.m b/objectivec/Tests/GPBUnittestProtos.m
index 1c6eddf..37e4773 100644
--- a/objectivec/Tests/GPBUnittestProtos.m
+++ b/objectivec/Tests/GPBUnittestProtos.m
@@ -40,26 +40,16 @@
 #import "google/protobuf/MapProto2Unittest.pbobjc.m"
 #import "google/protobuf/MapUnittest.pbobjc.m"
 #import "google/protobuf/Unittest.pbobjc.m"
-#import "google/protobuf/UnittestArena.pbobjc.m"
-#import "google/protobuf/UnittestCustomOptions.pbobjc.m"
 #import "google/protobuf/UnittestCycle.pbobjc.m"
 #import "google/protobuf/UnittestDeprecated.pbobjc.m"
 #import "google/protobuf/UnittestDeprecatedFile.pbobjc.m"
-#import "google/protobuf/UnittestDropUnknownFields.pbobjc.m"
-#import "google/protobuf/UnittestEmbedOptimizeFor.pbobjc.m"
-#import "google/protobuf/UnittestEmpty.pbobjc.m"
-#import "google/protobuf/UnittestEnormousDescriptor.pbobjc.m"
 #import "google/protobuf/UnittestImport.pbobjc.m"
-#import "google/protobuf/UnittestImportLite.pbobjc.m"
 #import "google/protobuf/UnittestImportPublic.pbobjc.m"
 #import "google/protobuf/UnittestImportPublicLite.pbobjc.m"
-#import "google/protobuf/UnittestLite.pbobjc.m"
 #import "google/protobuf/UnittestMset.pbobjc.m"
 #import "google/protobuf/UnittestMsetWireFormat.pbobjc.m"
-#import "google/protobuf/UnittestNoGenericServices.pbobjc.m"
 #import "google/protobuf/UnittestObjc.pbobjc.m"
 #import "google/protobuf/UnittestObjcStartup.pbobjc.m"
-#import "google/protobuf/UnittestOptimizeFor.pbobjc.m"
 #import "google/protobuf/UnittestPreserveUnknownEnum.pbobjc.m"
 #import "google/protobuf/UnittestRuntimeProto2.pbobjc.m"
 #import "google/protobuf/UnittestRuntimeProto3.pbobjc.m"