Nit: use the constant. (#374)

g-easy · web-flow · commit ea4b63f2fa8b · 2019-08-13T15:53:38.000+10:00
diff --git a/opencensus/common/internal/hostname.cc b/opencensus/common/internal/hostname.cc
@@ -53,7 +53,7 @@ std::string Hostname() {
   // SUSv2 says 255 is the limit for hostnames.
   char buf[256];
   if (gethostname(buf, sizeof(buf)) == -1) {
-    return "unknown_hostname";
+    return kUnknownHostname;
   }
   // gethostname() doesn't guarantee NUL termination.
   buf[sizeof(buf) - 1] = 0;

Original file line number	Diff line number	Diff line change
`@@ -53,7 +53,7 @@ std::string Hostname() {`
`53`	`53`	`// SUSv2 says 255 is the limit for hostnames.`
`54`	`54`	`char buf[256];`
`55`	`55`	`if (gethostname(buf, sizeof(buf)) == -1) {`
`56`		`- return "unknown_hostname";`
	`56`	`+ return kUnknownHostname;`
`57`	`57`	`}`
`58`	`58`	`// gethostname() doesn't guarantee NUL termination.`
`59`	`59`	`buf[sizeof(buf) - 1] = 0;`