Migrate page_load_metrics out of components.

components/page_load_metrics/browser/metrics_web_contents_observer.h

-// 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.
-
-#ifndef COMPONENTS_PAGE_LOAD_METRICS_BROWSER_METRICS_WEB_CONTENTS_OBSERVER_H_
-#define COMPONENTS_PAGE_LOAD_METRICS_BROWSER_METRICS_WEB_CONTENTS_OBSERVER_H_
-
-#include <map>
-#include <memory>
-#include <vector>
-
-#include "base/macros.h"
-#include "base/time/time.h"
-#include "components/page_load_metrics/browser/page_load_metrics_observer.h"
-#include "components/page_load_metrics/common/page_load_timing.h"
-#include "content/public/browser/render_widget_host.h"
-#include "content/public/browser/web_contents.h"
-#include "content/public/browser/web_contents_observer.h"
-#include "content/public/browser/web_contents_user_data.h"
-#include "net/base/net_errors.h"
-#include "third_party/WebKit/public/web/WebInputEvent.h"
-
-namespace content {
-class NavigationHandle;
-class RenderFrameHost;
-}  // namespace content
-
-namespace IPC {
-class Message;
-}  // namespace IPC
-
-namespace page_load_metrics {
-
-class PageLoadTracker;
-
-namespace internal {
-
-extern const char kErrorEvents[];
-extern const char kAbortChainSizeReload[];
-extern const char kAbortChainSizeForwardBack[];
-extern const char kAbortChainSizeNewNavigation[];
-extern const char kAbortChainSizeNoCommit[];
-extern const char kAbortChainSizeSameURL[];
-
-}  // namespace internal
-
-// These errors are internal to the page_load_metrics subsystem and do not
-// reflect actual errors that occur during a page load.
-//
-// If you add elements to this enum, make sure you update the enum
-// value in histograms.xml. Only add elements to the end to prevent
-// inconsistencies between versions.
-enum InternalErrorLoadEvent {
-  // A timing IPC was sent from the renderer that did not line up with previous
-  // data we've received (i.e. navigation start is different or the timing
-  // struct is somehow invalid). This error can only occur once the IPC is
-  // vetted in other ways (see other errors).
-  ERR_BAD_TIMING_IPC,
-
-  // The following IPCs are not mutually exclusive.
-  //
-  // We received an IPC when we weren't tracking a committed load. This will
-  // often happen if we get an IPC from a bad URL scheme (that is, the renderer
-  // sent us an IPC from a navigation we don't care about).
-  ERR_IPC_WITH_NO_RELEVANT_LOAD,
-
-  // Received a notification from a frame that has been navigated away from.
-  ERR_IPC_FROM_WRONG_FRAME,
-
-  // We received an IPC even through the last committed url from the browser
-  // was not http/s. This can happen with the renderer sending IPCs for the
-  // new tab page. This will often come paired with
-  // ERR_IPC_WITH_NO_RELEVANT_LOAD.
-  ERR_IPC_FROM_BAD_URL_SCHEME,
-
-  // If we track a navigation, but the renderer sends us no IPCs. This could
-  // occur if the browser filters loads less aggressively than the renderer.
-  ERR_NO_IPCS_RECEIVED,
-
-  // Tracks frequency with which we record an abort time that occurred before
-  // navigation start. This is expected to happen in some cases (see comments in
-  // cc file for details). We use this error counter to understand how often it
-  // happens.
-  ERR_ABORT_BEFORE_NAVIGATION_START,
-
-  // A new navigation triggers abort updates in multiple trackers in
-  // |aborted_provisional_loads_|, when usually there should only be one (the
-  // navigation that just aborted because of this one). If this happens, the
-  // latest aborted load is used to track the chain size.
-  ERR_NAVIGATION_SIGNALS_MULIPLE_ABORTED_LOADS,
-
-  // Received user input without a relevant load. This error type is deprecated,
-  // as it is valid to receive user input without a relevant load. We leave the
-  // enum value here since it's also used in histogram recording, so it's
-  // important that we not re-use this enum entry for a different value.
-  DEPRECATED_ERR_USER_INPUT_WITH_NO_RELEVANT_LOAD,
-
-  // A TimeTicks value in the browser process has value less than
-  // navigation_start_. This could happen if navigation_start_ was computed in
-  // renderer process and the system clock has inter process time tick skew.
-  ERR_INTER_PROCESS_TIME_TICK_SKEW,
-
-  // Add values before this final count.
-  ERR_LAST_ENTRY,
-};
-
-// This class serves as a functional interface to various chrome// features.
-// Impl version is defined in chrome/browser/page_load_metrics.
-class PageLoadMetricsEmbedderInterface {
- public:
-  virtual ~PageLoadMetricsEmbedderInterface() {}
-  virtual bool IsPrerendering(content::WebContents* web_contents) = 0;
-  virtual bool IsNewTabPageUrl(const GURL& url) = 0;
-  virtual void RegisterObservers(PageLoadTracker* metrics) = 0;
-};
-
-// This class tracks a given page load, starting from navigation start /
-// provisional load, until a new navigation commits or the navigation fails.
-// MetricsWebContentsObserver manages a set of provisional PageLoadTrackers, as
-// well as a committed PageLoadTracker.
-class PageLoadTracker {
- public:
-  // Caller must guarantee that the embedder_interface pointer outlives this
-  // class. The PageLoadTracker must not hold on to
-  // currently_committed_load_or_null or navigation_handle beyond the scope of
-  // the constructor.
-  PageLoadTracker(bool in_foreground,
-                  PageLoadMetricsEmbedderInterface* embedder_interface,
-                  const GURL& currently_committed_url,
-                  content::NavigationHandle* navigation_handle,
-                  int aborted_chain_size,
-                  int aborted_chain_size_same_url);
-  ~PageLoadTracker();
-  void Redirect(content::NavigationHandle* navigation_handle);
-  void Commit(content::NavigationHandle* navigation_handle);
-  void FailedProvisionalLoad(content::NavigationHandle* navigation_handle);
-  void WebContentsHidden();
-  void WebContentsShown();
-
-  void OnInputEvent(const blink::WebInputEvent& event);
-
-  void NotifyClientRedirectTo(const PageLoadTracker& destination);
-
-  // Returns true if the timing was successfully updated.
-  bool UpdateTiming(const PageLoadTiming& timing,
-                    const PageLoadMetadata& metadata);
-
-  // Signals that we should stop tracking metrics for the associated page load.
-  // We may stop tracking a page load if it doesn't meet the criteria for
-  // tracking metrics in DidFinishNavigation.
-  void StopTracking();
-
-  int aborted_chain_size() const { return aborted_chain_size_; }
-  int aborted_chain_size_same_url() const {
-    return aborted_chain_size_same_url_;
-  }
-
-  UserAbortType abort_type() const { return abort_type_; }
-  base::TimeTicks abort_time() const { return abort_time_; }
-
-  void AddObserver(std::unique_ptr<PageLoadMetricsObserver> observer);
-
-  // If the user performs some abort-like action while we are tracking this page
-  // load, notify the tracker. Note that we may not classify this as an abort if
-  // we've already performed a first paint.
-  // is_certainly_browser_timestamp signifies if the timestamp passed is taken
-  // in the
-  // browser process or not. We need this to possibly clamp browser timestamp on
-  // a machine with inter process time tick skew.
-  void NotifyAbort(UserAbortType abort_type,
-                   base::TimeTicks timestamp,
-                   bool is_certainly_browser_timestamp);
-  void UpdateAbort(UserAbortType abort_type,
-                   base::TimeTicks timestamp,
-                   bool is_certainly_browser_timestamp);
-
-  // This method returns true if this page load has been aborted with type of
-  // ABORT_OTHER, and the |abort_cause_time| is within a sufficiently close
-  // delta to when it was aborted. Note that only provisional loads can be
-  // aborted with ABORT_OTHER. While this heuristic is coarse, it works better
-  // and is simpler than other feasible methods. See https://goo.gl/WKRG98.
-  bool IsLikelyProvisionalAbort(base::TimeTicks abort_cause_time);
-
-  bool MatchesOriginalNavigation(content::NavigationHandle* navigation_handle);
-
-  // Only valid to call post-commit.
-  const GURL& committed_url() const {
-    DCHECK(!commit_time_.is_null());
-    return url_;
-  }
-
-  base::TimeTicks navigation_start() const { return navigation_start_; }
-
-  PageLoadExtraInfo ComputePageLoadExtraInfo();
-
- private:
-  // This function converts a TimeTicks value taken in the browser process
-  // to navigation_start_ if:
-  // - base::TimeTicks is not comparable across processes because the clock
-  // is not system wide monotonic.
-  // - *event_time < navigation_start_
-  void ClampBrowserTimestampIfInterProcessTimeTickSkew(
-      base::TimeTicks* event_time);
-
-  void UpdateAbortInternal(UserAbortType abort_type,
-                           base::TimeTicks timestamp,
-                           bool is_certainly_browser_timestamp);
-
-  // If |final_navigation| is null, then this is an "unparented" abort chain,
-  // and represents a sequence of provisional aborts that never ends with a
-  // committed load.
-  void LogAbortChainHistograms(content::NavigationHandle* final_navigation);
-
-  // Whether we stopped tracking this navigation after it was initiated. We may
-  // stop tracking a navigation if it doesn't meet the criteria for tracking
-  // metrics in DidFinishNavigation.
-  bool did_stop_tracking_;
-
-  // The navigation start in TimeTicks, not the wall time reported by Blink.
-  const base::TimeTicks navigation_start_;
-
-  // Time this page load was committed. If this page load hasn't committed,
-  // |commit_time_| will be zero.
-  base::TimeTicks commit_time_;
-
-  // The URL of this page load. This is the provisional url before commit
-  // (before redirects), and the committed url after commit.
-  GURL url_;
-
-  std::unique_ptr<FailedProvisionalLoadInfo> failed_provisional_load_info_;
-
-  // Will be ABORT_NONE if we have not aborted this load yet. Otherwise will
-  // be the first abort action the user performed.
-  UserAbortType abort_type_;
-  base::TimeTicks abort_time_;
-
-  // We record separate metrics for events that occur after a background,
-  // because metrics like layout/paint are delayed artificially
-  // when they occur in the background.
-  base::TimeTicks background_time_;
-  base::TimeTicks foreground_time_;
-  bool started_in_foreground_;
-
-  PageLoadTiming timing_;
-  PageLoadMetadata metadata_;
-
-  // This is a subtle member. If a provisional load A gets aborted by
-  // provisional load B, which gets aborted by C that eventually commits, then
-  // there exists an abort chain of length 2, starting at A's navigation_start.
-  // This is useful because it allows histograming abort chain lengths based on
-  // what the last load's transition type is. i.e. holding down F-5 to spam
-  // reload will produce a long chain with the RELOAD transition.
-  const int aborted_chain_size_;
-
-  // This member counts consecutive provisional aborts that share a url. It will
-  // always be less than or equal to |aborted_chain_size_|.
-  const int aborted_chain_size_same_url_;
-
-  // Interface to chrome features. Must outlive the class.
-  PageLoadMetricsEmbedderInterface* const embedder_interface_;
-
-  std::vector<std::unique_ptr<PageLoadMetricsObserver>> observers_;
-
-  DISALLOW_COPY_AND_ASSIGN(PageLoadTracker);
-};
-
-// MetricsWebContentsObserver tracks page loads and loading metrics
-// related data based on IPC messages received from a
-// MetricsRenderFrameObserver.
-class MetricsWebContentsObserver
-    : public content::WebContentsObserver,
-      public content::WebContentsUserData<MetricsWebContentsObserver>,
-      public content::RenderWidgetHost::InputEventObserver {
- public:
-  // Note that the returned metrics is owned by the web contents.
-  static MetricsWebContentsObserver* CreateForWebContents(
-      content::WebContents* web_contents,
-      std::unique_ptr<PageLoadMetricsEmbedderInterface> embedder_interface);
-  MetricsWebContentsObserver(
-      content::WebContents* web_contents,
-      std::unique_ptr<PageLoadMetricsEmbedderInterface> embedder_interface);
-  ~MetricsWebContentsObserver() override;
-
-  // content::WebContentsObserver implementation:
-  bool OnMessageReceived(const IPC::Message& message,
-                         content::RenderFrameHost* render_frame_host) override;
-  void DidStartNavigation(
-      content::NavigationHandle* navigation_handle) override;
-  void DidFinishNavigation(
-      content::NavigationHandle* navigation_handle) override;
-  void DidRedirectNavigation(
-      content::NavigationHandle* navigation_handle) override;
-  void NavigationStopped() override;
-  void OnInputEvent(const blink::WebInputEvent& event) override;
-  void WasShown() override;
-  void WasHidden() override;
-  void RenderProcessGone(base::TerminationStatus status) override;
-  void RenderViewHostChanged(content::RenderViewHost* old_host,
-                             content::RenderViewHost* new_host) override;
-
-  // This getter function is required for testing.
-  const PageLoadExtraInfo GetPageLoadExtraInfoForCommittedLoad();
-
- private:
-  friend class content::WebContentsUserData<MetricsWebContentsObserver>;
-
-  void HandleFailedNavigationForTrackedLoad(
-      content::NavigationHandle* navigation_handle,
-      std::unique_ptr<PageLoadTracker> tracker);
-
-  void HandleCommittedNavigationForTrackedLoad(
-      content::NavigationHandle* navigation_handle,
-      std::unique_ptr<PageLoadTracker> tracker);
-
-  // Notify all loads, provisional and committed, that we performed an action
-  // that might abort them.
-  void NotifyAbortAllLoads(UserAbortType abort_type);
-  void NotifyAbortAllLoadsWithTimestamp(UserAbortType abort_type,
-                                        base::TimeTicks timestamp,
-                                        bool is_certainly_browser_timestamp);
-
-  // Register / Unregister input event callback to given RenderViewHost
-  void RegisterInputEventObserver(content::RenderViewHost* host);
-  void UnregisterInputEventObserver(content::RenderViewHost* host);
-
-  // Notify aborted provisional loads that a new navigation occurred. This is
-  // used for more consistent attribution tracking for aborted provisional
-  // loads. This method returns the provisional load that was likely aborted
-  // by this navigation, to help instantiate the new PageLoadTracker.
-  std::unique_ptr<PageLoadTracker> NotifyAbortedProvisionalLoadsNewNavigation(
-      content::NavigationHandle* new_navigation);
-
-  void OnTimingUpdated(content::RenderFrameHost*,
-                       const PageLoadTiming& timing,
-                       const PageLoadMetadata& metadata);
-
-  bool ShouldTrackNavigation(
-      content::NavigationHandle* navigation_handle) const;
-
-  // True if the web contents is currently in the foreground.
-  bool in_foreground_;
-
-  // The PageLoadTrackers must be deleted before the |embedder_interface_|,
-  // because they hold a pointer to the |embedder_interface_|.
-  std::unique_ptr<PageLoadMetricsEmbedderInterface> embedder_interface_;
-
-  // This map tracks all of the navigations ongoing that are not committed
-  // yet. Once a navigation is committed, it moves from the map to
-  // committed_load_. Note that a PageLoadTrackers NavigationHandle is only
-  // valid until commit time, when we remove it from the map.
-  std::map<content::NavigationHandle*, std::unique_ptr<PageLoadTracker>>
-      provisional_loads_;
-
-  // Tracks aborted provisional loads for a little bit longer than usual (one
-  // more navigation commit at the max), in order to better understand how the
-  // navigation failed. This is because most provisional loads are destroyed
-  // and vanish before we get signal about what caused the abort (new
-  // navigation, stop button, etc.).
-  std::vector<std::unique_ptr<PageLoadTracker>> aborted_provisional_loads_;
-
-  std::unique_ptr<PageLoadTracker> committed_load_;
-
-  // Has the MWCO observed at least one navigation?
-  bool has_navigated_;
-
-  DISALLOW_COPY_AND_ASSIGN(MetricsWebContentsObserver);
-};
-
-}  // namespace page_load_metrics
-
-#endif  // COMPONENTS_PAGE_LOAD_METRICS_BROWSER_METRICS_WEB_CONTENTS_OBSERVER_H_