Bug 979566 - Profiler: Convert usleep to nanosleep. r=bgirard

tools/profiler/platform-linux.cc

@@ -588,8 +588,19 @@ void TickSample::PopulateContext(void* aContext)
   }
 }
 
+// WARNING: Works with values up to 1 second
 void OS::SleepMicro(int microseconds)
 {
-  usleep(microseconds);
+  struct timespec ts;
+  ts.tv_sec  = 0;
+  ts.tv_nsec = microseconds * 1000UL;
+
+  while (true) {
+    // in the case of interrupt we keep waiting
+    // nanosleep puts the remaining to back into ts
+    if (!nanosleep(&ts, &ts) || errno != EINTR) {
+      return;
+    }
+  }
 }