[metrics] Avoid string copy
We pass by const reference instead of copy.
Test: TreeHugger
Change-Id: Icf9ed05d001d5ed07f6160a06d5295501bfeeb05
diff --git a/libartbase/base/metrics/metrics_common.cc b/libartbase/base/metrics/metrics_common.cc
index c650fdf..c29605e 100644
--- a/libartbase/base/metrics/metrics_common.cc
+++ b/libartbase/base/metrics/metrics_common.cc
@@ -167,7 +167,7 @@
LOG_STREAM(level_) << GetAndResetBuffer();
}
-FileBackend::FileBackend(std::string filename) : filename_{filename} {}
+FileBackend::FileBackend(const std::string& filename) : filename_{filename} {}
void FileBackend::BeginReport(uint64_t timestamp_since_start_ms) {
GetAndResetBuffer();