Prevent stubs from being installed in java.lang.reflect.Proxy.<init>.

This CL is a better fix for proxy tracing and undoes the changes in
https://android-review.googlesource.com/#/c/103025/

Change-Id: Ie82bb49f07774bd08a6720ddbe5b1f8ee9363acf
diff --git a/runtime/instrumentation.cc b/runtime/instrumentation.cc
index ae42284..9c6f8c4 100644
--- a/runtime/instrumentation.cc
+++ b/runtime/instrumentation.cc
@@ -121,6 +121,13 @@
     // Do not change stubs for these methods.
     return;
   }
+  std::string temp;
+  // Note that the Proxy class itself is not a proxy class.
+  if (strcmp(method->GetDeclaringClass()->GetDescriptor(&temp), "Ljava/lang/reflect/Proxy;") == 0 &&
+      method->IsConstructor()) {
+    // Do not stub Proxy.<init>.
+    return;
+  }
   const void* new_portable_code;
   const void* new_quick_code;
   bool uninstall = !entry_exit_stubs_installed_ && !interpreter_stubs_installed_;