Fix clang-tidy performance warnings in system/vold.

* Use const reference type for for-loop index variables
  to avoid unnecessary copy.

Bug: 30413223
Change-Id: Id4d980ae8afec1374fc3be0b23f1c6a39bff86e0
Test: build with WITH_TIDY=1

1 files changed, 1 insertions, 1 deletions

diff --git a/Utils.cpp b/Utils.cpp
index a9bddfa..97dea79 100644
--- a/Utils.cpp
+++ b/Utils.cpp
@@ -208,7 +208,7 @@ static status_t readMetadata(const std::string& path, std::string& fsType,
     }
 
     char value[128];
-    for (auto line : output) {
+    for (const auto& line : output) {
         // Extract values from blkid output, if defined
         const char* cline = line.c_str();
         const char* start = strstr(cline, "TYPE=");