Factor PageLoadTracker into its own header and impl files.

chrome/browser/page_load_metrics/page_load_tracker.cc

Index: chrome/browser/page_load_metrics/page_load_tracker.cc
diff --git a/chrome/browser/page_load_metrics/metrics_web_contents_observer.cc b/chrome/browser/page_load_metrics/page_load_tracker.cc
similarity index 63%
copy from chrome/browser/page_load_metrics/metrics_web_contents_observer.cc
copy to chrome/browser/page_load_metrics/page_load_tracker.cc
index c58e4d517126fcb62f499914f485d4707e4332f8..1ae615a77ed7268ffae00c73071a2e9829c972c1 100644
--- a/chrome/browser/page_load_metrics/metrics_web_contents_observer.cc
+++ b/chrome/browser/page_load_metrics/page_load_tracker.cc
@@ -1,38 +1,25 @@
-// Copyright 2015 The Chromium Authors. All rights reserved.
+// Copyright 2016 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/page_load_metrics/metrics_web_contents_observer.h"
+#include "chrome/browser/page_load_metrics/page_load_tracker.h"
 
 #include <algorithm>
 #include <ostream>
 #include <string>
 #include <utility>
 
-#include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/metrics/user_metrics.h"
-#include "chrome/browser/page_load_metrics/browser_page_track_decider.h"
+#include "chrome/browser/page_load_metrics/page_load_metrics_embedder_interface.h"
 #include "chrome/browser/page_load_metrics/page_load_metrics_util.h"
-#include "chrome/common/page_load_metrics/page_load_metrics_messages.h"
 #include "chrome/common/page_load_metrics/page_load_timing.h"
-#include "content/public/browser/browser_thread.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_handle.h"
-#include "content/public/browser/render_frame_host.h"
-#include "content/public/browser/render_view_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 "ipc/ipc_message.h"
-#include "ipc/ipc_message_macros.h"
 #include "ui/base/page_transition_types.h"
 
-DEFINE_WEB_CONTENTS_USER_DATA_KEY(
-    page_load_metrics::MetricsWebContentsObserver);
-
 // This macro invokes the specified method on each observer, passing the
 // variable length arguments as the method's arguments, and removes the observer
 // from the list of observers if the given method returns STOP_OBSERVING.
@@ -70,6 +57,42 @@ const char kPageLoadCompletedAfterAppBackground[] =
 
 }  // namespace internal
 
+void RecordInternalError(InternalErrorLoadEvent event) {
+  UMA_HISTOGRAM_ENUMERATION(internal::kErrorEvents, event, ERR_LAST_ENTRY);
+}
+
+// TODO(csharrison): Add a case for client side redirects, which is what JS
+// initiated window.location / window.history navigations get set to.
+UserAbortType AbortTypeForPageTransition(ui::PageTransition transition) {
+  if (transition & ui::PAGE_TRANSITION_CLIENT_REDIRECT) {
+    return ABORT_CLIENT_REDIRECT;
+  }
+  if (ui::PageTransitionCoreTypeIs(transition, ui::PAGE_TRANSITION_RELOAD))
+    return ABORT_RELOAD;
+  if (transition & ui::PAGE_TRANSITION_FORWARD_BACK)
+    return ABORT_FORWARD_BACK;
+  if (ui::PageTransitionIsNewNavigation(transition))
+    return ABORT_NEW_NAVIGATION;
+  NOTREACHED()
+      << "AbortTypeForPageTransition received unexpected ui::PageTransition: "
+      << transition;
+  return ABORT_OTHER;
+}
+
+void LogAbortChainSameURLHistogram(int aborted_chain_size_same_url) {
+  if (aborted_chain_size_same_url > 0) {
+    UMA_HISTOGRAM_COUNTS(internal::kAbortChainSizeSameURL,
+                         aborted_chain_size_same_url);
+  }
+}
+
+// TODO(crbug.com/617904): Browser initiated navigations should have
+// HasUserGesture() set to true. Update this once we get enough data from just
+// renderer initiated aborts.
+bool IsNavigationUserInitiated(content::NavigationHandle* handle) {
+  return handle->HasUserGesture();
+}
+
 namespace {
 
 // Helper to allow use of Optional<> values in LOG() messages.
@@ -215,40 +238,11 @@ bool IsValidPageLoadTiming(const PageLoadTiming& timing) {
   return true;
 }
 
-void RecordInternalError(InternalErrorLoadEvent event) {
-  UMA_HISTOGRAM_ENUMERATION(internal::kErrorEvents, event, ERR_LAST_ENTRY);
-}
-
 void RecordAppBackgroundPageLoadCompleted(bool completed_after_background) {
   UMA_HISTOGRAM_BOOLEAN(internal::kPageLoadCompletedAfterAppBackground,
                         completed_after_background);
 }
 
-// TODO(csharrison): Add a case for client side redirects, which is what JS
-// initiated window.location / window.history navigations get set to.
-UserAbortType AbortTypeForPageTransition(ui::PageTransition transition) {
-  if (transition & ui::PAGE_TRANSITION_CLIENT_REDIRECT) {
-    return ABORT_CLIENT_REDIRECT;
-  }
-  if (ui::PageTransitionCoreTypeIs(transition, ui::PAGE_TRANSITION_RELOAD))
-    return ABORT_RELOAD;
-  if (transition & ui::PAGE_TRANSITION_FORWARD_BACK)
-    return ABORT_FORWARD_BACK;
-  if (ui::PageTransitionIsNewNavigation(transition))
-    return ABORT_NEW_NAVIGATION;
-  NOTREACHED()
-      << "AbortTypeForPageTransition received unexpected ui::PageTransition: "
-      << transition;
-  return ABORT_OTHER;
-}
-
-void LogAbortChainSameURLHistogram(int aborted_chain_size_same_url) {
-  if (aborted_chain_size_same_url > 0) {
-    UMA_HISTOGRAM_COUNTS(internal::kAbortChainSizeSameURL,
-                         aborted_chain_size_same_url);
-  }
-}
-
 void DispatchObserverTimingCallbacks(PageLoadMetricsObserver* observer,
                                      const PageLoadTiming& last_timing,
                                      const PageLoadTiming& new_timing,
@@ -281,13 +275,6 @@ void DispatchObserverTimingCallbacks(PageLoadMetricsObserver* observer,
     observer->OnLoadingBehaviorObserved(extra_info);
 }
 
-// TODO(crbug.com/617904): Browser initiated navigations should have
-// HasUserGesture() set to true. Update this once we get enough data from just
-// renderer initiated aborts.
-bool IsNavigationUserInitiated(content::NavigationHandle* handle) {
-  return handle->HasUserGesture();
-}
-
 }  // namespace
 
 PageLoadTracker::PageLoadTracker(
@@ -688,412 +675,4 @@ void PageLoadTracker::UpdateAbortInternal(UserAbortType abort_type,
   }
 }
 
-// static
-MetricsWebContentsObserver::MetricsWebContentsObserver(
-    content::WebContents* web_contents,
-    std::unique_ptr<PageLoadMetricsEmbedderInterface> embedder_interface)
-    : content::WebContentsObserver(web_contents),
-      in_foreground_(false),
-      embedder_interface_(std::move(embedder_interface)),
-      has_navigated_(false) {
-  RegisterInputEventObserver(web_contents->GetRenderViewHost());
-}
-
-MetricsWebContentsObserver* MetricsWebContentsObserver::CreateForWebContents(
-    content::WebContents* web_contents,
-    std::unique_ptr<PageLoadMetricsEmbedderInterface> embedder_interface) {
-  DCHECK(web_contents);
-
-  MetricsWebContentsObserver* metrics = FromWebContents(web_contents);
-  if (!metrics) {
-    metrics = new MetricsWebContentsObserver(web_contents,
-                                             std::move(embedder_interface));
-    web_contents->SetUserData(UserDataKey(), metrics);
-  }
-  return metrics;
-}
-
-MetricsWebContentsObserver::~MetricsWebContentsObserver() {
-  // TODO(csharrison): Use a more user-initiated signal for CLOSE.
-  NotifyAbortAllLoads(ABORT_CLOSE, false);
-}
-
-void MetricsWebContentsObserver::RegisterInputEventObserver(
-    content::RenderViewHost* host) {
-  if (host != nullptr)
-    host->GetWidget()->AddInputEventObserver(this);
-}
-
-void MetricsWebContentsObserver::UnregisterInputEventObserver(
-    content::RenderViewHost* host) {
-  if (host != nullptr)
-    host->GetWidget()->RemoveInputEventObserver(this);
-}
-
-void MetricsWebContentsObserver::RenderViewHostChanged(
-    content::RenderViewHost* old_host,
-    content::RenderViewHost* new_host) {
-  UnregisterInputEventObserver(old_host);
-  RegisterInputEventObserver(new_host);
-}
-
-bool MetricsWebContentsObserver::OnMessageReceived(
-    const IPC::Message& message,
-    content::RenderFrameHost* render_frame_host) {
-  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP_WITH_PARAM(MetricsWebContentsObserver, message,
-                                   render_frame_host)
-    IPC_MESSAGE_HANDLER(PageLoadMetricsMsg_TimingUpdated, OnTimingUpdated)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
-}
-
-void MetricsWebContentsObserver::WillStartNavigationRequest(
-    content::NavigationHandle* navigation_handle) {
-  if (!navigation_handle->IsInMainFrame())
-    return;
-
-  std::unique_ptr<PageLoadTracker> last_aborted =
-      NotifyAbortedProvisionalLoadsNewNavigation(navigation_handle);
-
-  int chain_size_same_url = 0;
-  int chain_size = 0;
-  if (last_aborted) {
-    if (last_aborted->MatchesOriginalNavigation(navigation_handle)) {
-      chain_size_same_url = last_aborted->aborted_chain_size_same_url() + 1;
-    } else if (last_aborted->aborted_chain_size_same_url() > 0) {
-      LogAbortChainSameURLHistogram(
-          last_aborted->aborted_chain_size_same_url());
-    }
-    chain_size = last_aborted->aborted_chain_size() + 1;
-  }
-
-  if (!ShouldTrackNavigation(navigation_handle))
-    return;
-
-  // Pass in the last committed url to the PageLoadTracker. If the MWCO has
-  // never observed a committed load, use the last committed url from this
-  // WebContent's opener. This is more accurate than using referrers due to
-  // referrer sanitizing and origin referrers. Note that this could potentially
-  // be inaccurate if the opener has since navigated.
-  content::WebContents* opener = web_contents()->GetOpener();
-  const GURL& opener_url =
-      !has_navigated_ && opener
-          ? web_contents()->GetOpener()->GetLastCommittedURL()
-          : GURL::EmptyGURL();
-  const GURL& currently_committed_url =
-      committed_load_ ? committed_load_->committed_url() : opener_url;
-  has_navigated_ = true;
-
-  // We can have two provisional loads in some cases. E.g. a same-site
-  // navigation can have a concurrent cross-process navigation started
-  // from the omnibox.
-  DCHECK_GT(2ul, provisional_loads_.size());
-  // Passing raw pointers to observers_ and embedder_interface_ is safe because
-  // the MetricsWebContentsObserver owns them both list and they are torn down
-  // after the PageLoadTracker. The PageLoadTracker does not hold on to
-  // committed_load_ or navigation_handle beyond the scope of the constructor.
-  provisional_loads_.insert(std::make_pair(
-      navigation_handle,
-      base::MakeUnique<PageLoadTracker>(
-          in_foreground_, embedder_interface_.get(), currently_committed_url,
-          navigation_handle, chain_size, chain_size_same_url)));
-}
-
-void MetricsWebContentsObserver::OnRequestComplete(
-    content::ResourceType resource_type,
-    bool was_cached,
-    int net_error) {
-  // For simplicity, only count subresources. Navigations are hard to attribute
-  // here because we won't have a committed load by the time data streams in
-  // from the IO thread.
-  if (resource_type == content::RESOURCE_TYPE_MAIN_FRAME &&
-      net_error != net::OK) {
-    return;
-  }
-  if (!committed_load_)
-    return;
-  committed_load_->OnLoadedSubresource(was_cached);
-}
-
-const PageLoadExtraInfo
-MetricsWebContentsObserver::GetPageLoadExtraInfoForCommittedLoad() {
-  DCHECK(committed_load_);
-  return committed_load_->ComputePageLoadExtraInfo();
-}
-
-void MetricsWebContentsObserver::DidFinishNavigation(
-    content::NavigationHandle* navigation_handle) {
-  if (!navigation_handle->IsInMainFrame())
-    return;
-
-  std::unique_ptr<PageLoadTracker> finished_nav(
-      std::move(provisional_loads_[navigation_handle]));
-  provisional_loads_.erase(navigation_handle);
-
-  // Ignore same-page navigations.
-  if (navigation_handle->HasCommitted() && navigation_handle->IsSamePage()) {
-    if (finished_nav)
-      finished_nav->StopTracking();
-    return;
-  }
-
-  // Ignore internally generated aborts for navigations with HTTP responses that
-  // don't commit, such as HTTP 204 responses and downloads.
-  if (!navigation_handle->HasCommitted() &&
-      navigation_handle->GetNetErrorCode() == net::ERR_ABORTED &&
-      navigation_handle->GetResponseHeaders()) {
-    if (finished_nav)
-      finished_nav->StopTracking();
-    return;
-  }
-
-  const bool should_track =
-      finished_nav && ShouldTrackNavigation(navigation_handle);
-
-  if (finished_nav && !should_track)
-    finished_nav->StopTracking();
-
-  if (navigation_handle->HasCommitted()) {
-    // Notify other loads that they may have been aborted by this committed
-    // load. is_certainly_browser_timestamp is set to false because
-    // NavigationStart() could be set in either the renderer or browser process.
-    NotifyAbortAllLoadsWithTimestamp(
-        AbortTypeForPageTransition(navigation_handle->GetPageTransition()),
-        IsNavigationUserInitiated(navigation_handle),
-        navigation_handle->NavigationStart(), false);
-
-    if (should_track) {
-      HandleCommittedNavigationForTrackedLoad(navigation_handle,
-                                              std::move(finished_nav));
-    } else {
-      committed_load_.reset();
-    }
-  } else if (should_track) {
-    HandleFailedNavigationForTrackedLoad(navigation_handle,
-                                         std::move(finished_nav));
-  }
-}
-
-// Handle a pre-commit error. Navigations that result in an error page will be
-// ignored.
-void MetricsWebContentsObserver::HandleFailedNavigationForTrackedLoad(
-    content::NavigationHandle* navigation_handle,
-    std::unique_ptr<PageLoadTracker> tracker) {
-  tracker->FailedProvisionalLoad(navigation_handle);
-
-  net::Error error = navigation_handle->GetNetErrorCode();
-
-  // net::OK: This case occurs when the NavigationHandle finishes and reports
-  // !HasCommitted(), but reports no net::Error. This should not occur
-  // pre-PlzNavigate, but afterwards it should represent the navigation stopped
-  // by the user before it was ready to commit.
-  // net::ERR_ABORTED: An aborted provisional load has error
-  // net::ERR_ABORTED.
-  if ((error == net::OK) || (error == net::ERR_ABORTED)) {
-    tracker->NotifyAbort(ABORT_OTHER, false, base::TimeTicks::Now(), true);
-    aborted_provisional_loads_.push_back(std::move(tracker));
-  }
-}
-
-void MetricsWebContentsObserver::HandleCommittedNavigationForTrackedLoad(
-    content::NavigationHandle* navigation_handle,
-    std::unique_ptr<PageLoadTracker> tracker) {
-  if (!navigation_handle->HasUserGesture() &&
-      (navigation_handle->GetPageTransition() &
-       ui::PAGE_TRANSITION_CLIENT_REDIRECT) != 0 &&
-      committed_load_)
-    committed_load_->NotifyClientRedirectTo(*tracker);
-
-  committed_load_ = std::move(tracker);
-  committed_load_->Commit(navigation_handle);
-}
-
-void MetricsWebContentsObserver::NavigationStopped() {
-  // TODO(csharrison): Use a more user-initiated signal for STOP.
-  NotifyAbortAllLoads(ABORT_STOP, false);
-}
-
-void MetricsWebContentsObserver::OnInputEvent(
-    const blink::WebInputEvent& event) {
-  // Ignore browser navigation or reload which comes with type Undefined.
-  if (event.type == blink::WebInputEvent::Type::Undefined)
-    return;
-
-  if (committed_load_)
-    committed_load_->OnInputEvent(event);
-}
-
-void MetricsWebContentsObserver::FlushMetricsOnAppEnterBackground() {
-  // Signal to observers that we've been backgrounded, in cases where the
-  // FlushMetricsOnAppEnterBackground callback gets invoked before the
-  // associated WasHidden callback.
-  WasHidden();
-
-  if (committed_load_)
-    committed_load_->FlushMetricsOnAppEnterBackground();
-  for (const auto& kv : provisional_loads_) {
-    kv.second->FlushMetricsOnAppEnterBackground();
-  }
-  for (const auto& tracker : aborted_provisional_loads_) {
-    tracker->FlushMetricsOnAppEnterBackground();
-  }
-}
-
-void MetricsWebContentsObserver::DidRedirectNavigation(
-    content::NavigationHandle* navigation_handle) {
-  if (!navigation_handle->IsInMainFrame())
-    return;
-  auto it = provisional_loads_.find(navigation_handle);
-  if (it == provisional_loads_.end())
-    return;
-  it->second->Redirect(navigation_handle);
-}
-
-void MetricsWebContentsObserver::WasShown() {
-  if (in_foreground_)
-    return;
-  in_foreground_ = true;
-  if (committed_load_)
-    committed_load_->WebContentsShown();
-  for (const auto& kv : provisional_loads_) {
-    kv.second->WebContentsShown();
-  }
-}
-
-void MetricsWebContentsObserver::WasHidden() {
-  if (!in_foreground_)
-    return;
-  in_foreground_ = false;
-  if (committed_load_)
-    committed_load_->WebContentsHidden();
-  for (const auto& kv : provisional_loads_) {
-    kv.second->WebContentsHidden();
-  }
-}
-
-// This will occur when the process for the main RenderFrameHost exits, either
-// normally or from a crash. We eagerly log data from the last committed load if
-// we have one. Don't notify aborts here because this is probably not user
-// initiated. If it is (e.g. browser shutdown), other code paths will take care
-// of notifying.
-void MetricsWebContentsObserver::RenderProcessGone(
-    base::TerminationStatus status) {
-  // Other code paths will be run for normal renderer shutdown. Note that we
-  // sometimes get the STILL_RUNNING value on fast shutdown.
-  if (status == base::TERMINATION_STATUS_NORMAL_TERMINATION ||
-      status == base::TERMINATION_STATUS_STILL_RUNNING) {
-    return;
-  }
-
-  // If this is a crash, eagerly log the aborted provisional loads and the
-  // committed load. |provisional_loads_| don't need to be destroyed here
-  // because their lifetime is tied to the NavigationHandle.
-  committed_load_.reset();
-  aborted_provisional_loads_.clear();
-}
-
-void MetricsWebContentsObserver::NotifyAbortAllLoads(UserAbortType abort_type,
-                                                     bool user_initiated) {
-  NotifyAbortAllLoadsWithTimestamp(abort_type, user_initiated,
-                                   base::TimeTicks::Now(), true);
-}
-
-void MetricsWebContentsObserver::NotifyAbortAllLoadsWithTimestamp(
-    UserAbortType abort_type,
-    bool user_initiated,
-    base::TimeTicks timestamp,
-    bool is_certainly_browser_timestamp) {
-  if (committed_load_) {
-    committed_load_->NotifyAbort(abort_type, user_initiated, timestamp,
-                                 is_certainly_browser_timestamp);
-  }
-  for (const auto& kv : provisional_loads_) {
-    kv.second->NotifyAbort(abort_type, user_initiated, timestamp,
-                           is_certainly_browser_timestamp);
-  }
-  for (const auto& tracker : aborted_provisional_loads_) {
-    if (tracker->IsLikelyProvisionalAbort(timestamp)) {
-      tracker->UpdateAbort(abort_type, user_initiated, timestamp,
-                           is_certainly_browser_timestamp);
-    }
-  }
-  aborted_provisional_loads_.clear();
-}
-
-std::unique_ptr<PageLoadTracker>
-MetricsWebContentsObserver::NotifyAbortedProvisionalLoadsNewNavigation(
-    content::NavigationHandle* new_navigation) {
-  // If there are multiple aborted loads that can be attributed to this one,
-  // just count the latest one for simplicity. Other loads will fall into the
-  // OTHER bucket, though there shouldn't be very many.
-  if (aborted_provisional_loads_.size() == 0)
-    return nullptr;
-  if (aborted_provisional_loads_.size() > 1)
-    RecordInternalError(ERR_NAVIGATION_SIGNALS_MULIPLE_ABORTED_LOADS);
-
-  std::unique_ptr<PageLoadTracker> last_aborted_load =
-      std::move(aborted_provisional_loads_.back());
-  aborted_provisional_loads_.pop_back();
-
-  base::TimeTicks timestamp = new_navigation->NavigationStart();
-  if (last_aborted_load->IsLikelyProvisionalAbort(timestamp)) {
-    last_aborted_load->UpdateAbort(
-        AbortTypeForPageTransition(new_navigation->GetPageTransition()),
-        IsNavigationUserInitiated(new_navigation), timestamp, false);
-  }
-
-  aborted_provisional_loads_.clear();
-  return last_aborted_load;
-}
-
-void MetricsWebContentsObserver::OnTimingUpdated(
-    content::RenderFrameHost* render_frame_host,
-    const PageLoadTiming& timing,
-    const PageLoadMetadata& metadata) {
-  // We may receive notifications from frames that have been navigated away
-  // from. We simply ignore them.
-  if (render_frame_host != web_contents()->GetMainFrame()) {
-    RecordInternalError(ERR_IPC_FROM_WRONG_FRAME);
-    return;
-  }
-
-  // While timings arriving for the wrong frame are expected, we do not expect
-  // any of the errors below. Thus, we track occurrences of all errors below,
-  // rather than returning early after encountering an error.
-
-  bool error = false;
-  if (!committed_load_) {
-    RecordInternalError(ERR_IPC_WITH_NO_RELEVANT_LOAD);
-    error = true;
-  }
-
-  if (!web_contents()->GetLastCommittedURL().SchemeIsHTTPOrHTTPS()) {
-    RecordInternalError(ERR_IPC_FROM_BAD_URL_SCHEME);
-    error = true;
-  }
-
-  if (error)
-    return;
-
-  if (!committed_load_->UpdateTiming(timing, metadata)) {
-    // If the page load tracker cannot update its timing, something is wrong
-    // with the IPC (it's from another load, or it's invalid in some other way).
-    // We expect this to be a rare occurrence.
-    RecordInternalError(ERR_BAD_TIMING_IPC);
-  }
-}
-
-bool MetricsWebContentsObserver::ShouldTrackNavigation(
-    content::NavigationHandle* navigation_handle) const {
-  DCHECK(navigation_handle->IsInMainFrame());
-  DCHECK(!navigation_handle->HasCommitted() ||
-         !navigation_handle->IsSamePage());
-
-  return BrowserPageTrackDecider(embedder_interface_.get(), web_contents(),
-                                 navigation_handle).ShouldTrack();
-}
-
 }  // namespace page_load_metrics