Mute common case DexFile.isDexOptNeeded log spam

Bug: 18914409

(cherry picked from commit 9851595177fec4d5e328f201f1992719fb40db2a)

Change-Id: If9b741ff8e09400a421e0a0ba1bc0d9ef13a9f99
diff --git a/runtime/native/dalvik_system_DexFile.cc b/runtime/native/dalvik_system_DexFile.cc
index a8b297d..3298b46 100644
--- a/runtime/native/dalvik_system_DexFile.cc
+++ b/runtime/native/dalvik_system_DexFile.cc
@@ -294,7 +294,10 @@
                                                         nullptr,
                                                         false, &error_msg));
   if (oat_file.get() == nullptr) {
-    if (kReasonLogging) {
+    // Note that even though this is kDexoptNeeded, we use
+    // kVerboseLogging instead of the usual kReasonLogging since it is
+    // the common case on first boot and very spammy.
+    if (kVerboseLogging) {
       LOG(INFO) << "DexFile_isDexOptNeeded failed to open oat file '" << oat_filename
           << "' for file location '" << filename << "': " << error_msg;
     }