Fix "unreachable code" warnings (MSVC warning 4702) in content/.

content/common/page_state_serialization_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <math.h>
 
 #include "base/base64.h"
 #include "base/file_util.h"
 #include "base/path_service.h"
 #include "base/pickle.h"
@@ skipping 340 matching lines @@
   p.WriteInt(1);
   p.WriteInt(blink::WebHTTPBody::Element::TypeData);
 
   std::string s(static_cast<const char*>(p.data()), p.size());
 
   ExplodedPageState output;
   EXPECT_FALSE(DecodePageState(s, &output));
 }
 
 TEST_F(PageStateSerializationTest, DumpExpectedPageStateForBackwardsCompat) {
-  // Comment out this return statement to enable this code.  Use this code to
-  // generate data, based on the current serialization format, for the
-  // BackwardsCompat_vXX tests.
-  return;
-
+  // Change to #if 1 to enable this code.  Use this code to generate data, based
+  // on the current serialization format, for the BackwardsCompat_vXX tests.
+#if 0
   ExplodedPageState state;
   PopulatePageStateForBackwardsCompatTest(&state);
 
   std::string encoded;
   EXPECT_TRUE(EncodePageState(state, &encoded));
 
   std::string base64;
   base::Base64Encode(encoded, &base64);
 
   base::FilePath path;
   PathService::Get(base::DIR_TEMP, &path);
   path = path.AppendASCII("expected.dat");
 
   FILE* fp = base::OpenFile(path, "wb");
   ASSERT_TRUE(fp);
 
   const size_t kRowSize = 76;
   for (size_t offset = 0; offset < base64.size(); offset += kRowSize) {
     size_t length = std::min(base64.size() - offset, kRowSize);
     std::string segment(&base64[offset], length);
     segment.push_back('\n');
     ASSERT_EQ(1U, fwrite(segment.data(), segment.size(), 1, fp));
   }
 
   fclose(fp);
+#endif
 }
 
 #if !defined(OS_ANDROID)
 // TODO(darin): Re-enable for Android once this test accounts for systems with
 //              a device scale factor not equal to 2.
 TEST_F(PageStateSerializationTest, BackwardsCompat_v11) {
   TestBackwardsCompat(11);
 }
 #endif
 
@@ skipping 16 matching lines @@
 TEST_F(PageStateSerializationTest, BackwardsCompat_v16) {
   TestBackwardsCompat(16);
 }
 
 TEST_F(PageStateSerializationTest, BackwardsCompat_v18) {
   TestBackwardsCompat(18);
 }
 
 }  // namespace
 }  // namespace content