Upstream the clipboard implementation for Android

base/android/jni_android.cc

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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 "base/android/jni_android.h"
 
 #include <map>
 
 #include "base/atomicops.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
@@ skipping 138 matching lines @@
 jfieldID GetFieldID(JNIEnv* env,
                     jclass clazz,
                     const char* field,
                     const char* jni_signature) {
   jfieldID id = env->GetFieldID(clazz, field, jni_signature);
   DCHECK(id) << field;
   CheckException(env);
   return id;
 }
 
-bool CheckException(JNIEnv* env) {
-  if (env->ExceptionCheck() == JNI_FALSE)
+bool HasException(JNIEnv* env) {
+  return env->ExceptionCheck() != JNI_FALSE;
+}
+
+bool ClearException(JNIEnv* env) {
+  if (!HasException(env))
     return false;
-  env->ExceptionDescribe();
   env->ExceptionClear();
   return true;
 }
 
+void CheckException(JNIEnv* env) {
+  if (HasException(env)) {
+    env->ExceptionDescribe();
+    CHECK(false);
+  }
+}
+
 }  // namespace android
 }  // namespace base