Replace FilePath with base::FilePath in some more top level directories.

tools/android/device_stats_monitor/device_stats_monitor.cc

Index: tools/android/device_stats_monitor/device_stats_monitor.cc
diff --git a/tools/android/device_stats_monitor/device_stats_monitor.cc b/tools/android/device_stats_monitor/device_stats_monitor.cc
index ebf17234b549f8a4a1d1c226525494197000adc5..c24a6d94b44b9c4da0d345b5d8cdebd15aedb381 100644
--- a/tools/android/device_stats_monitor/device_stats_monitor.cc
+++ b/tools/android/device_stats_monitor/device_stats_monitor.cc
@@ -39,8 +39,8 @@ class DeviceStatsMonitor {
   // would affect the results.
   void Start(int hz) {
     const int sample_interval = 1000000 / hz;
-    const FilePath io_stats_path(kIOStatsPath);
-    const FilePath cpu_stats_path(kCPUStatsPath);
+    const base::FilePath io_stats_path(kIOStatsPath);
+    const base::FilePath cpu_stats_path(kCPUStatsPath);
     std::string out;
     while (record_) {
       out.clear();
@@ -65,7 +65,7 @@ class DeviceStatsMonitor {
   }
 
  private:
-  const FilePath out_path_;
+  const base::FilePath out_path_;
   std::vector<std::string> samples_;
   bool record_;