Add more systracing everywhere

Added to:
JIT
DexFile functions
Oat file manager

Added helper ScopedTrace to prevent errors and reduce excess code.

Bug: 27502458

(cherry picked from commit dabdc0fe183d4684f3cf4d70cb09d318cff81b42)

Change-Id: Ifaeff8913d79eefc797380987d13cc00456266f8
diff --git a/runtime/jit/profile_saver.cc b/runtime/jit/profile_saver.cc
index ab26f6f..bd58157 100644
--- a/runtime/jit/profile_saver.cc
+++ b/runtime/jit/profile_saver.cc
@@ -17,6 +17,7 @@
 #include "profile_saver.h"
 
 #include "art_method-inl.h"
+#include "base/systrace.h"
 #include "scoped_thread_state_change.h"
 #include "oat_file_manager.h"
 
@@ -93,6 +94,7 @@
 }
 
 bool ProfileSaver::ProcessProfilingInfo() {
+  ScopedTrace trace(__PRETTY_FUNCTION__);
   uint64_t last_update_time_ns = jit_code_cache_->GetLastUpdateTimeNs();
   if (!first_profile_ && last_update_time_ns - code_cache_last_update_time_ns_
           < kMinimumTimeBetweenCodeCacheUpdatesNs) {