Make CPU profiler do not hog 100% of CPU.

src/base/platform/platform.h

Index: src/base/platform/platform.h
diff --git a/src/base/platform/platform.h b/src/base/platform/platform.h
index 2d837baff61078fedd74626491dc28db8d3bf930..2b21a39055d4684a3cad026bae361d5760fc1b69 100644
--- a/src/base/platform/platform.h
+++ b/src/base/platform/platform.h
@@ -190,8 +190,8 @@ class OS {
   // Get the Alignment guaranteed by Allocate().
   static size_t AllocateAlignment();
 
-  // Sleep for a number of milliseconds.
-  static void Sleep(const int milliseconds);
+  // Sleep for a specified time interval.
+  static void Sleep(TimeDelta interval);
 
   // Abort the current process.
   static void Abort();