Make all FATAL-related output appear as 'F' log output.

Previously most of the spew belonging to a FATAL would be 'E' because
Runtime::Abort() used LOG(ERROR) to avoid recursion.

Change-Id: If8f62586c302c239e827c5235ed58ee8fe6e8f5e
diff --git a/src/runtime.cc b/src/runtime.cc
index 579e591..3f6bcca 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -138,7 +138,7 @@
   // Many people have difficulty distinguish aborts from crashes,
   // so be explicit.
   AbortState state;
-  LOG(ERROR) << Dumpable<AbortState>(state);
+  LOG(INTERNAL_FATAL) << Dumpable<AbortState>(state);
 
   // Perform any platform-specific pre-abort actions.
   PlatformAbort(file, line);