Store URLs in WebappDataStorage, and purge them when history is cleared.

chrome/browser/android/webapps/webapp_registry.cc

 // Copyright 2015 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 "chrome/browser/android/webapps/webapp_registry.h"
 
 #include <jni.h>
 
 #include "base/android/context_utils.h"
 #include "base/android/jni_android.h"
 #include "base/callback.h"
 #include "chrome/browser/io_thread.h"
 #include "content/public/browser/browser_thread.h"
 #include "jni/WebappRegistry_jni.h"
 
 // static
 void WebappRegistry::UnregisterWebapps(
     const base::Closure& callback) {
   JNIEnv* env = base::android::AttachCurrentThread();
   uintptr_t callback_pointer = reinterpret_cast<uintptr_t>(
       new base::Closure(callback));
 
   Java_WebappRegistry_unregisterAllWebapps(
       env,
       base::android::GetApplicationContext(),
       callback_pointer);
 }
 
+// static
+void WebappRegistry::ClearWebappHistory(const base::Closure& callback) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  uintptr_t callback_pointer = reinterpret_cast<uintptr_t>(
+      new base::Closure(callback));
+
+  Java_WebappRegistry_clearWebappHistory(
+      env,
+      base::android::GetApplicationContext(),
+      callback_pointer);
+}
+
 // Callback used by Java when all web apps have been unregistered.
 void OnWebappsUnregistered(JNIEnv* env,
                            const JavaParamRef<jclass>& klass,
                            jlong jcallback) {
   base::Closure* callback = reinterpret_cast<base::Closure*>(jcallback);
   callback->Run();
   delete callback;
 }
 
+// Callback used by Java when all web app last used times have been cleared.
+void OnClearedWebappHistory(JNIEnv* env,
+                                  const JavaParamRef<jclass>& klass,

[gone, 2016/03/08 22:40:39]

nit: indentation; common convention is to use clazz

+                                  jlong jcallback) {
+  base::Closure* callback = reinterpret_cast<base::Closure*>(jcallback);
+  callback->Run();
+  delete callback;
+}
+
 // static
 bool WebappRegistry::RegisterWebappRegistry(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }