Consistently use base::OpenFile.

Change-Id: Ib9275182c984084f1d4f7e63faf380888b3c0a76

src/trace_processor/trace_processor_shell.cc

diff --git a/src/trace_processor/trace_processor_shell.cc b/src/trace_processor/trace_processor_shell.cc
index 487ac8f..05540e1 100644
--- a/src/trace_processor/trace_processor_shell.cc
+++ b/src/trace_processor/trace_processor_shell.cc
@@ -202,8 +202,7 @@
   TraceProcessor::Config config;
   config.optimization_mode = OptimizationMode::kMaxBandwidth;
   TraceProcessor tp(config);
-  base::ScopedFile fd;
-  fd.reset(open(trace_file_path, O_RDONLY));
+  base::ScopedFile fd(base::OpenFile(trace_file_path, O_RDONLY));
   PERFETTO_CHECK(fd);
 
   // Load the trace in chunks using async IO. We create a simple pipeline where,