predictors: Add a origin for prefetch requests, remove the URL/host settings.

chrome/browser/predictors/resource_prefetch_common.h

 // 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.
 
 #ifndef CHROME_BROWSER_PREDICTORS_RESOURCE_PREFETCH_COMMON_H_
 #define CHROME_BROWSER_PREDICTORS_RESOURCE_PREFETCH_COMMON_H_
 
 #include <stddef.h>
 
 #include "base/time/time.h"
@@ skipping 14 matching lines @@
 bool IsSpeculativeResourcePrefetchingEnabled(
     Profile* profile,
     ResourcePrefetchPredictorConfig* config);
 
 // Represents the type of key based on which prefetch data is stored.
 enum PrefetchKeyType {
   PREFETCH_KEY_TYPE_HOST,
   PREFETCH_KEY_TYPE_URL
 };
 
+// Indicates what caused the prefetch request.
+enum class PrefetchOrigin { NAVIGATION, EXTERNAL };
+
 // Represents a single navigation for a render frame.
 struct NavigationID {
   NavigationID();
   NavigationID(int render_process_id,
                int render_frame_id,
                const GURL& main_frame_url);
   NavigationID(const NavigationID& other);
   explicit NavigationID(content::WebContents* web_contents);
   bool operator<(const NavigationID& rhs) const;
   bool operator==(const NavigationID& rhs) const;
 
   bool IsSameRenderer(const NavigationID& other) const;
 
   // Returns true iff the render_process_id_, render_frame_id_ and
   // frame_url_ has been set correctly.
   bool is_valid() const;
 
   int render_process_id;
   int render_frame_id;
   GURL main_frame_url;
 
   // NOTE: Even though we store the creation time here, it is not used during
   // comparison of two NavigationIDs because it cannot always be determined
   // correctly.
   base::TimeTicks creation_time;
 };
 
-// Represents the config for the resource prefetch prediction algorithm. It is
-// useful for running experiments.
+// Represents the config for the resource prefetch prediction algorithm.
 struct ResourcePrefetchPredictorConfig {
   // Initializes the config with default values.
   ResourcePrefetchPredictorConfig();
   ResourcePrefetchPredictorConfig(const ResourcePrefetchPredictorConfig& other);
   ~ResourcePrefetchPredictorConfig();
 
   // The mode the prefetcher is running in. Forms a bit map.
   enum Mode {
-    URL_LEARNING = 1 << 0,
-    HOST_LEARNING = 1 << 1,
-    URL_PREFETCHING = 1 << 2,  // Should also turn on URL_LEARNING.
-    HOST_PREFETCHING = 1 << 3  // Should also turn on HOST_LEARNING.
+    LEARNING = 1 << 0,
+    PREFETCHING_FOR_NAVIGATION = 1 << 2,  // Also enables LEARNING.
+    PREFETCHING_FOR_EXTERNAL = 1 << 3     // Also enables LEARNING.
   };
   int mode;
 
   // Helpers to deal with mode.
   bool IsLearningEnabled() const;
-  bool IsPrefetchingEnabled(Profile* profile) const;
-  bool IsURLLearningEnabled() const;
-  bool IsHostLearningEnabled() const;
-  bool IsURLPrefetchingEnabled(Profile* profile) const;
-  bool IsHostPrefetchingEnabled(Profile* profile) const;
+  bool IsPrefetchingEnabledForSomeOrigin(Profile* profile) const;
+  bool IsPrefetchingEnabledForOrigin(Profile* profile,
+                                     PrefetchOrigin origin) const;
 
   bool IsLowConfidenceForTest() const;
   bool IsHighConfidenceForTest() const;
   bool IsMoreResourcesEnabledForTest() const;
   bool IsSmallDBEnabledForTest() const;
 
   // If a navigation hasn't seen a load complete event in this much time, it
   // is considered abandoned.
   size_t max_navigation_lifetime_seconds;
 
@@ skipping 20 matching lines @@
   // Maximum number of prefetches that can be inflight for a single navigation.
   size_t max_prefetches_inflight_per_navigation;
   // Maximum number of prefetches that can be inflight for a host for a single
   // navigation.
   size_t max_prefetches_inflight_per_host_per_navigation;
 };
 
 }  // namespace predictors
 
 #endif  // CHROME_BROWSER_PREDICTORS_RESOURCE_PREFETCH_COMMON_H_