Android: cleanup jni_android to minimize external dependencies.

content/browser/android/web_contents_observer_android.cc

 // Copyright (c) 2012 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.
 
 #include "content/browser/android/web_contents_observer_android.h"
 
 #include <string>
 
 #include <jni.h>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
 #include "base/android/scoped_java_ref.h"
 #include "content/browser/android/content_view_core_impl.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
 #include "jni/WebContentsObserverAndroid_jni.h"
 
 using base::android::AttachCurrentThread;
 using base::android::ScopedJavaLocalRef;
 using base::android::ConvertUTF8ToJavaString;
 using base::android::ConvertUTF16ToJavaString;
-using base::android::HasClass;
 
 namespace content {
 
 WebContentsObserverAndroid::WebContentsObserverAndroid(
     JNIEnv* env,
     jobject obj,
     WebContents* web_contents)
     : WebContentsObserver(web_contents),
       weak_java_observer_(env, obj){
 }
@@ skipping 209 matching lines @@
 
   Java_WebContentsObserverAndroid_didFailLoad(
       env, obj.obj(),
       is_provisional_load,
       is_main_frame,
       error_code,
       jstring_error_description.obj(), jstring_url.obj());
 }
 
 bool RegisterWebContentsObserverAndroid(JNIEnv* env) {
-  if (!HasClass(env, kWebContentsObserverAndroidClassPath)) {
-    DLOG(ERROR) << "Unable to find class WebContentsObserverAndroid!";
-    return false;
-  }
   return RegisterNativesImpl(env);
 }
 }  // namespace content