Fix GetQuickCodeFor to return actual code pointer if it exists.

If the compiled entry point is the interpreter entry point, the code
now tries to get oat code for it before returning.

Change-Id: Iea1cec1ed003aadd71b432cc405fc81509bc644a
diff --git a/src/instrumentation.cc b/src/instrumentation.cc
index f36cb8c..8598d6d 100644
--- a/src/instrumentation.cc
+++ b/src/instrumentation.cc
@@ -384,7 +384,8 @@
   if (LIKELY(!instrumentation_stubs_installed_)) {
     const void* code = method->GetEntryPointFromCompiledCode();
     DCHECK(code != NULL);
-    if (LIKELY(code != GetResolutionTrampoline(runtime->GetClassLinker()))) {
+    if (LIKELY(code != GetResolutionTrampoline(runtime->GetClassLinker()) &&
+               code != GetInterpreterEntryPoint())) {
       return code;
     }
   }