Add -verbose:interpreter

Adds a mode to track what methods are being interpreted. Good
for debugging interpreter usage during app startup.

Bug: 130185360
Test: test-art-host

Change-Id: I8119f79e534cdad7d6a72d4f01115a288e9c8d9a
diff --git a/runtime/interpreter/interpreter.cc b/runtime/interpreter/interpreter.cc
index db116f5..ce242a7 100644
--- a/runtime/interpreter/interpreter.cc
+++ b/runtime/interpreter/interpreter.cc
@@ -321,6 +321,7 @@
   DCHECK(!method->SkipAccessChecks() || !method->MustCountLocks());
 
   bool transaction_active = Runtime::Current()->IsActiveTransaction();
+  VLOG(interpreter) << "Interpreting " << method->PrettyMethod();
   if (LIKELY(method->SkipAccessChecks())) {
     // Enter the "without access check" interpreter.
     if (kInterpreterImplKind == kMterpImplKind) {