Only set precache.last_time when precache ran.

chrome/browser/android/precache/precache_launcher.cc

 // 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.
 
 #include "chrome/browser/android/precache/precache_launcher.h"
 
 #include <jni.h>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_weak_ref.h"
@@ skipping 48 matching lines @@
 
 void PrecacheLauncher::Start(JNIEnv* env, jobject obj) {
   // TODO(bengr): Add integration tests for the whole feature.
   Profile* profile = GetProfile();
 
   PrecacheManager* precache_manager = GetPrecacheManager(profile);
   history::HistoryService* hs = HistoryServiceFactory::GetForProfile(
       profile, ServiceAccessType::IMPLICIT_ACCESS);
 
   if (precache_manager == nullptr || hs == nullptr) {
-    OnPrecacheCompleted();
+    OnPrecacheCompleted(false);
     return;
   }
 
   precache_manager->StartPrecaching(
       base::Bind(&PrecacheLauncher::OnPrecacheCompleted,
                  weak_factory_.GetWeakPtr()),
       *hs);
 }
 
 void PrecacheLauncher::Cancel(JNIEnv* env, jobject obj) {
   Profile* profile = GetProfile();
   PrecacheManager* precache_manager = GetPrecacheManager(profile);
 
   precache_manager->CancelPrecaching();
 }
 
-void PrecacheLauncher::OnPrecacheCompleted() {
+void PrecacheLauncher::OnPrecacheCompleted(bool try_again_soon) {
   JNIEnv* env = AttachCurrentThread();
   Java_PrecacheLauncher_onPrecacheCompletedCallback(
-      env, weak_java_precache_launcher_.get(env).obj());
+      env, weak_java_precache_launcher_.get(env).obj(),
+      try_again_soon ? JNI_TRUE : JNI_FALSE);
 }
 
 static jlong Init(JNIEnv* env, jobject obj) {
   return reinterpret_cast<intptr_t>(new PrecacheLauncher(env, obj));
 }
 
 // Must be run on the UI thread.
 static jboolean ShouldRun(JNIEnv* env, jobject obj) {
   Profile* profile = GetProfile();
   PrecacheManager* precache_manager = GetPrecacheManager(profile);
   return precache_manager && precache_manager->ShouldRun();
 }
 
 bool RegisterPrecacheLauncher(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }