CL for src perf tryjob to run page_cycler_v2.intl_ko_th_vi benchmark on all-android platform(s)

chrome/browser/renderer_host/predictor_resource_throttle.cc

-// 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/renderer_host/predictor_resource_throttle.h"
-
-#include "base/memory/ptr_util.h"
-#include "chrome/browser/net/predictor.h"
-#include "chrome/browser/profiles/profile_io_data.h"
-#include "content/public/browser/resource_request_info.h"
-#include "content/public/common/resource_type.h"
-#include "net/url_request/redirect_info.h"
-#include "net/url_request/url_request.h"
-#include "url/gurl.h"
-
-namespace {
-
-bool IsNavigationRequest(net::URLRequest* request) {
-  content::ResourceType resource_type =
-      content::ResourceRequestInfo::ForRequest(request)->GetResourceType();
-  return resource_type == content::RESOURCE_TYPE_MAIN_FRAME ||
-         resource_type == content::RESOURCE_TYPE_SUB_FRAME;
-}
-
-}  // namespace
-
-PredictorResourceThrottle::PredictorResourceThrottle(
-    net::URLRequest* request,
-    chrome_browser_net::Predictor* predictor)
-    : request_(request), predictor_(predictor) {}
-
-PredictorResourceThrottle::~PredictorResourceThrottle() {}
-
-// static
-std::unique_ptr<PredictorResourceThrottle>
-PredictorResourceThrottle::MaybeCreate(net::URLRequest* request,
-                                       ProfileIOData* io_data) {
-  if (io_data->GetPredictor()) {
-    return base::WrapUnique(
-        new PredictorResourceThrottle(request, io_data->GetPredictor()));
-  }
-  return nullptr;
-}
-
-void PredictorResourceThrottle::WillStartRequest(bool* defer) {
-  GURL request_scheme_host(
-      chrome_browser_net::Predictor::CanonicalizeUrl(request_->url()));
-  if (request_scheme_host.is_empty())
-    return;
-
-  // Learn what URLs are likely to be needed during next startup.
-  // TODO(csharrison): Rename this method, as this code path is used for more
-  // than just navigation requests.
-  predictor_->LearnAboutInitialNavigation(request_scheme_host);
-
-  const content::ResourceRequestInfo* info =
-      content::ResourceRequestInfo::ForRequest(request_);
-  DCHECK(info);
-  content::ResourceType resource_type = info->GetResourceType();
-  const GURL& referring_scheme_host =
-      GURL(request_->referrer()).GetWithEmptyPath();
-
-  // Learn about our referring URL, for use in the future. Only learn
-  // subresource relationships.
-  if (!referring_scheme_host.is_empty() &&
-      resource_type != content::RESOURCE_TYPE_MAIN_FRAME &&
-      predictor_->timed_cache()->WasRecentlySeen(referring_scheme_host)) {
-    predictor_->LearnFromNavigation(referring_scheme_host, request_scheme_host);
-  }
-
-  // Subresources for main frames are predicted when navigation starts, in
-  // PredictorTabHelper, so only handle predictions for subframes here.
-  // If the referring host is equal to the request host, then the predictor has
-  // already made any/all predictions when navigating to the referring host.
-  // Don't update the RecentlySeen() time because the timed cache is already
-  // populated (with the correct timeout) based on the initial navigation.
-  if (IsNavigationRequest(request_) &&
-      referring_scheme_host != request_scheme_host) {
-    predictor_->timed_cache()->SetRecentlySeen(request_scheme_host);
-    if (resource_type == content::RESOURCE_TYPE_SUB_FRAME) {
-      predictor_->PredictFrameSubresources(request_scheme_host,
-                                           request_->first_party_for_cookies());
-    }
-  }
-}
-
-void PredictorResourceThrottle::WillRedirectRequest(
-    const net::RedirectInfo& redirect_info,
-    bool* defer) {
-  GURL new_scheme_host(
-      chrome_browser_net::Predictor::CanonicalizeUrl(redirect_info.new_url));
-  GURL original_scheme_host(request_->original_url().GetWithEmptyPath());
-  // Note: This is comparing a canonicalizd URL with a non-canonicalized URL.
-  // This should be fixed and the idea of canonicalization revisited.
-  if (new_scheme_host == original_scheme_host || new_scheme_host.is_empty())
-    return;
-  // Don't learn or predict subresource redirects.
-  if (!IsNavigationRequest(request_))
-    return;
-
-  // Don't learn from redirects that take path as an argument, but do
-  // learn from short-hand typing entries, such as "cnn.com" redirects to
-  // "www.cnn.com".  We can't just check for has_path(), as a mere "/"
-  // will count as a path, so we check that the path is at most a "/"
-  // (1 character long) to decide the redirect is "definitive" and has no
-  // significant path.
-  // TODO(jar): It may be ok to learn from all redirects, as the adaptive
-  // system will not respond until several identical redirects have taken
-  // place.  Hence a use of a path (that changes) wouldn't really be
-  // learned from anyway.
-  if (request_->original_url().path().length() <= 1 &&
-      predictor_->timed_cache()->WasRecentlySeen(original_scheme_host)) {
-    // TODO(jar): These definite redirects could be learned much faster.
-    predictor_->LearnFromNavigation(original_scheme_host, new_scheme_host);
-  }
-
-  predictor_->timed_cache()->SetRecentlySeen(new_scheme_host);
-  predictor_->PredictFrameSubresources(
-      new_scheme_host, redirect_info.new_first_party_for_cookies);
-}
-
-const char* PredictorResourceThrottle::GetNameForLogging() const {
-  return "PredictorResourceThrottle";
-}