Fix problem with empty profiles.

This fixes an issue where a profile file was created by the installer
but never written by the runtime.  This happens when profiles are off.
This caused the compiler to think that there are no methods worthy
of compilation and skipped everything.

Bug: 13960166
Change-Id: I4c4598d4746218e21ca949112071dc1424d7d1f9
diff --git a/runtime/profiler.cc b/runtime/profiler.cc
index 77e7316..7b117f4 100644
--- a/runtime/profiler.cc
+++ b/runtime/profiler.cc
@@ -588,7 +588,7 @@
     return false;
   }
   if (st.st_size == 0) {
-    return true;  // empty profiles are ok.
+    return false;  // Empty profiles are invalid.
   }
   std::ifstream in(fileName.c_str());
   if (!in) {