tracing/services: Set the process name for new-style utility services

Utility services are now started in a slightly different way by
UtilityThreadImpl. In the past, their TraceLog process names were set
in UtilityServiceFactory, which is no longer involved for most services.

So, also set the process name in the new service binder.

Bug: 1040525
Change-Id: Ib8900350460ee2711303519d705de3de361fb3f2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1993349Reviewed-by: Ken Rockot <rockot@google.com>
Reviewed-by: Nasko Oskov <nasko@chromium.org>
Commit-Queue: Eric Seckler <eseckler@chromium.org>
Auto-Submit: Eric Seckler <eseckler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#730094}

content/utility/utility_thread_impl.cc

@@ -15,6 +15,7 @@
 #include "base/memory/scoped_refptr.h"
 #include "base/optional.h"
 #include "base/sequenced_task_runner.h"
+#include "base/trace_event/trace_log.h"
 #include "build/build_config.h"
 #include "content/child/child_process.h"
 #include "content/public/utility/content_utility_client.h"
@@ -43,8 +44,13 @@ class ServiceBinderImpl {
     // was running in the process.
     static auto* service_name_crash_key = base::debug::AllocateCrashKeyString(
         "service-name", base::debug::CrashKeySize::Size32);
-    base::debug::SetCrashKeyString(service_name_crash_key,
-                                   receiver->interface_name().value());
+    const std::string& service_name = receiver->interface_name().value();
+    base::debug::SetCrashKeyString(service_name_crash_key, service_name);
+
+    // Traces should also indicate the service name.
+    auto* trace_log = base::trace_event::TraceLog::GetInstance();
+    if (trace_log->IsProcessNameEmpty())
+      trace_log->set_process_name("Service: " + service_name);
 
     // We watch for and terminate on PEER_CLOSED, but we also terminate if the
     // watcher is cancelled (meaning the local endpoint was closed rather than