[Prerender] first contentful paint histograms.

chrome/browser/prerender/prerender_test_utils.cc

 // Copyright (c) 2012 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/prerender/prerender_test_utils.h"
 
 #include <memory>
 #include <set>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/command_line.h"
-#include "base/strings/string_split.h"
+#include "base/memory/ptr_util.h"
+#include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/loader/chrome_resource_dispatcher_host_delegate.h"
 #include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/browser/prerender/prerender_manager_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/safe_browsing/local_database_manager.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/generated_resources.h"
@@ skipping 444 matching lines @@
   contents_ = nullptr;
   final_status_ = contents->final_status();
   stopped_ = true;
   stop_loop_.Quit();
   // If there is a WaitForLoads call and it has yet to see the expected number
   // of loads, stop the loop so the test fails instead of timing out.
   if (load_waiter_)
     load_waiter_->Quit();
 }
 
+// static
+FirstContentfulPaintManagerWaiter* FirstContentfulPaintManagerWaiter::Create(
+    PrerenderManager* manager) {
+  auto fcp_waiter = base::WrapUnique(new FirstContentfulPaintManagerWaiter());
+  auto fcp_waiter_ptr = fcp_waiter.get();
+  manager->AddObserver(std::move(fcp_waiter));
+  return fcp_waiter_ptr;
+}
+
+FirstContentfulPaintManagerWaiter::FirstContentfulPaintManagerWaiter()
+    : saw_fcp_(false) {}
+
+FirstContentfulPaintManagerWaiter::~FirstContentfulPaintManagerWaiter() {}
+
+void FirstContentfulPaintManagerWaiter::OnFirstContentfulPaint() {
+  saw_fcp_ = true;
+  if (waiter_)
+    waiter_->Quit();
+}
+
+void FirstContentfulPaintManagerWaiter::Wait() {
+  if (saw_fcp_)
+    return;
+  waiter_ = base::MakeUnique<base::RunLoop>();
+  waiter_->Run();
+  waiter_.reset();
+}
+
 TestPrerenderContentsFactory::TestPrerenderContentsFactory() {}
 
 TestPrerenderContentsFactory::~TestPrerenderContentsFactory() {
   EXPECT_TRUE(expected_contents_queue_.empty());
 }
 
 std::unique_ptr<TestPrerender>
 TestPrerenderContentsFactory::ExpectPrerenderContents(
     FinalStatus final_status) {
   std::unique_ptr<TestPrerender> handle(new TestPrerender());
@@ skipping 221 matching lines @@
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   std::unique_ptr<net::URLRequestInterceptor> interceptor(
       new HangingFirstRequestInterceptor(file, callback));
   net::URLRequestFilter::GetInstance()->AddUrlInterceptor(
       url, std::move(interceptor));
 }
 
 }  // namespace test_utils
 
 }  // namespace prerender