Cleanup: Better constify some strings in net/.

net/tools/quic/test_tools/http_message.cc

Index: net/tools/quic/test_tools/http_message.cc
diff --git a/net/tools/quic/test_tools/http_message.cc b/net/tools/quic/test_tools/http_message.cc
index 9bd3cffc3120cff25f47a2e9a9a31ac34bf886f5..cb322550a8816d986b0a01eb07e7f42a39ede59f 100644
--- a/net/tools/quic/test_tools/http_message.cc
+++ b/net/tools/quic/test_tools/http_message.cc
@@ -20,20 +20,20 @@ namespace test {
 
 namespace {
 
-//const char* kContentEncoding = "content-encoding";
-const char* kContentLength = "content-length";
-const char* kTransferCoding = "transfer-encoding";
+//const char kContentEncoding[] = "content-encoding";
+const char kContentLength[] = "content-length";
+const char kTransferCoding[] = "transfer-encoding";
 
 // Both kHTTPVersionString and kMethodString arrays are constructed to match
 // the enum values defined in Version and Method of HTTPMessage.
-const char* kHTTPVersionString[] = {
+const char* const kHTTPVersionString[] = {
   "",
   "HTTP/0.9",
   "HTTP/1.0",
   "HTTP/1.1"
 };
 
-const char* kMethodString[] = {
+const char* const kMethodString[] = {
   "",
   "OPTIONS",
   "GET",