Make class lookup lazy in jni_generator when using lazy method lookup.

base/android/jni_generator/testSingleJNIAdditionalImport.golden

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file is autogenerated by
 //     base/android/jni_generator/jni_generator.py
 // For
 //     org/chromium/foo/Foo
 
 #ifndef org_chromium_foo_Foo_JNI
 #define org_chromium_foo_Foo_JNI
 
 #include <jni.h>
 
 #include "base/android/jni_generator/jni_generator_helper.h"
 
 #include "base/android/jni_int_wrapper.h"
 
 // Step 1: forward declarations.
 namespace {
 const char kFooClassPath[] = "org/chromium/foo/Foo";
+#if __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-function"
+#endif
 // Leaking this jclass as we cannot use LazyInstance from some threads.
 jclass g_Foo_clazz = NULL;
+jclass Foo_clazz(JNIEnv*) { return g_Foo_clazz; }
+#if __clang__
+#pragma clang diagnostic pop
+#endif
 
 }  // namespace
 
 static void DoSomething(JNIEnv* env, jclass jcaller,
     jobject callback);
 
 // Step 2: method stubs.
 
 static base::subtle::AtomicWord g_Foo_calledByNative = 0;
 static void Java_Foo_calledByNative(JNIEnv* env, jobject callback) {
   /* Must call RegisterNativesImpl()  */
-  CHECK_CLAZZ(env, g_Foo_clazz,
-      g_Foo_clazz);
+  CHECK_CLAZZ(env, Foo_clazz(env),
+      Foo_clazz(env));
   jmethodID method_id =
       base::android::MethodID::LazyGet<
       base::android::MethodID::TYPE_STATIC>(
-      env, g_Foo_clazz,
+      env, Foo_clazz(env),
       "calledByNative",
 
 "("
 "Lorg/chromium/foo/Bar$Callback;"
 ")"
 "V",
       &g_Foo_calledByNative);
 
-     env->CallStaticVoidMethod(g_Foo_clazz,
+     env->CallStaticVoidMethod(Foo_clazz(env),
           method_id, callback);
   jni_generator::CheckException(env);
 
 }
 
 // Step 3: RegisterNatives.
 
 static const JNINativeMethod kMethodsFoo[] = {
     { "nativeDoSomething",
 "("
 "Lorg/chromium/foo/Bar$Callback;"
 ")"
 "V", reinterpret_cast<void*>(DoSomething) },
 };
 
 static bool RegisterNativesImpl(JNIEnv* env) {
   g_Foo_clazz = reinterpret_cast<jclass>(env->NewGlobalRef(
       base::android::GetClass(env, kFooClassPath).obj()));
 
   const int kMethodsFooSize = arraysize(kMethodsFoo);
 
-  if (env->RegisterNatives(g_Foo_clazz,
+  if (env->RegisterNatives(Foo_clazz(env),
                            kMethodsFoo,
                            kMethodsFooSize) < 0) {
     jni_generator::HandleRegistrationError(
-        env, g_Foo_clazz, __FILE__);
+        env, Foo_clazz(env), __FILE__);
     return false;
   }
 
   return true;
 }
 
 #endif  // org_chromium_foo_Foo_JNI