Log warnings when test server fails to start

On some bots the license server is failing to start, so log a warning
when it fails to hopefully indicate what is going wrong.

Bug: 976083
Test: compiles
Change-Id: Idff11ea2885289608c549396b6e11e28e095ed72
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1940954Reviewed-by: Xiaohan Wang <xhwang@chromium.org>
Commit-Queue: John Rummell <jrummell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#719793}

chrome/browser/media/test_license_server.cc

@@ -27,20 +27,20 @@ bool TestLicenseServer::Start() {
     return true;
 
   if (!server_config_->IsPlatformSupported()) {
-    DVLOG(0) << "License server is not supported on current platform.";
+    LOG(WARNING) << "License server is not supported on current platform.";
     return false;
   }
 
   base::CommandLine command_line(base::CommandLine::NO_PROGRAM);
   if (!server_config_->GetServerCommandLine(&command_line)) {
-    DVLOG(0) << "Could not get server command line to launch.";
+    LOG(WARNING) << "Could not get server command line to launch.";
     return false;
   }
 
   base::Optional<base::EnvironmentMap> env =
       server_config_->GetServerEnvironment();
   if (!env) {
-    DVLOG(0) << "Could not get server environment variables.";
+    LOG(WARNING) << "Could not get server environment variables.";
     return false;
   }
 
@@ -50,7 +50,7 @@ bool TestLicenseServer::Start() {
   launch_options.environment = std::move(*env);
   license_server_process_ = base::LaunchProcess(command_line, launch_options);
   if (!license_server_process_.IsValid()) {
-    DVLOG(0) << "Failed to start test license server!";
+    LOG(WARNING) << "Failed to start test license server!";
     return false;
   }
   return true;