predictors: Introduce GlowplugPredictor.

chrome/browser/predictors/glowplug_config.cc

+// Copyright 2017 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/predictors/glowplug_config.h"
+#include "chrome/browser/predictors/resource_prefetch_common.h"
+
+namespace predictors {
+
+bool IsGlowplugEnabled(Profile* profile, GlowplugPredictorConfig* config) {
+  return IsSpeculativeResourcePrefetchingEnabled(profile, config);
+}
+
+GlowplugPredictorConfig::GlowplugPredictorConfig()
+    : mode(0),
+      max_navigation_lifetime_seconds(60),
+      max_urls_to_track(500),
+      max_hosts_to_track(200),
+      min_url_visit_count(2),
+      max_resources_per_entry(50),
+      max_origins_per_entry(50),
+      max_consecutive_misses(3),
+      max_redirect_consecutive_misses(5),
+      min_resource_confidence_to_trigger_prefetch(0.7f),
+      min_resource_hits_to_trigger_prefetch(2),
+      max_prefetches_inflight_per_navigation(5),
+      max_prefetches_inflight_per_host_per_navigation(3),
+      is_url_learning_enabled(false),
+      is_manifests_enabled(false),
+      is_origin_learning_enabled(false) {}
+
+GlowplugPredictorConfig::GlowplugPredictorConfig(
+    const GlowplugPredictorConfig& other) = default;
+
+GlowplugPredictorConfig::~GlowplugPredictorConfig() = default;
+
+bool GlowplugPredictorConfig::IsLearningEnabled() const {
+  return (mode & LEARNING) > 0;
+}
+
+bool GlowplugPredictorConfig::IsPrefetchingEnabledForSomeOrigin(
+    Profile* profile) const {
+  int mask = PREFETCHING_FOR_NAVIGATION | PREFETCHING_FOR_EXTERNAL;
+  return internal::IsPrefetchingEnabledInternal(profile, mode, mask);
+}
+
+bool GlowplugPredictorConfig::IsPrefetchingEnabledForOrigin(
+    Profile* profile,
+    PrefetchOrigin origin) const {
+  int mask = 0;
+  switch (origin) {
+    case PrefetchOrigin::NAVIGATION:
+      mask = PREFETCHING_FOR_NAVIGATION;
+      break;
+    case PrefetchOrigin::EXTERNAL:
+      mask = PREFETCHING_FOR_EXTERNAL;
+      break;
+  }
+  return internal::IsPrefetchingEnabledInternal(profile, mode, mask);
+}
+
+bool GlowplugPredictorConfig::IsLowConfidenceForTest() const {
+  return min_url_visit_count == 1 &&
+         std::abs(min_resource_confidence_to_trigger_prefetch - 0.5f) < 1e-6 &&
+         min_resource_hits_to_trigger_prefetch == 1;
+}
+
+bool GlowplugPredictorConfig::IsHighConfidenceForTest() const {
+  return min_url_visit_count == 3 &&
+         std::abs(min_resource_confidence_to_trigger_prefetch - 0.9f) < 1e-6 &&
+         min_resource_hits_to_trigger_prefetch == 3;
+}
+
+bool GlowplugPredictorConfig::IsMoreResourcesEnabledForTest() const {
+  return max_resources_per_entry == 100;
+}
+
+bool GlowplugPredictorConfig::IsSmallDBEnabledForTest() const {
+  return max_urls_to_track == 200 && max_hosts_to_track == 100;
+}
+
+}  // namespace predictors